Fixed 39 build warnings due to upcoming Scala 3 changes and previously deprecated methods.

[jverbus]

Builds are generating a lot of warnings (39 in total) due to current and future deprecations. I've addressed all warnings in this PR.

Here is an example build before these changes:

(base) jv@Jamess-MBP isolation-forest % ./gradlew clean build --no-build-cache                         


> Configure project :
Building version '3.1.1'
  - reason: shipkit-auto-version deduced version based on previous tag: '3.1.0'

> Configure project :isolation-forest
Scala version: 2.13.14
Spark version: 3.5.1

> Task :isolation-forest:compileScala
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/main/scala/com/linkedin/relevance/isolationforest/IsolationForest.scala:49: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method head,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/main/scala/com/linkedin/relevance/isolationforest/IsolationForest.scala:97: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method toDS,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/main/scala/com/linkedin/relevance/isolationforest/IsolationForest.scala:109: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method get,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/main/scala/com/linkedin/relevance/isolationforest/IsolationForest.scala:127: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method get,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/main/scala/com/linkedin/relevance/isolationforest/IsolationForestModelReadWrite.scala:302: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method extractParamMap,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/main/scala/com/linkedin/relevance/isolationforest/IsolationTree.scala:127: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method nextDouble,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/main/scala/com/linkedin/relevance/isolationforest/IsolationForestModelReadWrite.scala:257: method copyArrayToImmutableIndexedSeq in class LowPriorityImplicits2 is deprecated (since 2.13.0): implicit conversions from Array to immutable.IndexedSeq are implemented by copying; use `toIndexedSeq` explicitly if you want to copy, or use the more efficient non-copying ArraySeq.unsafeWrapArray
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/main/scala/com/linkedin/relevance/isolationforest/IsolationTree.scala:50: method seq in trait Iterable is deprecated (since 2.13.0): Iterable.seq always returns the iterable itself
8 warnings found

> Task :isolation-forest:compileTestScala
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/BaggedPointTest.scala:48: procedure syntax is deprecated: instead, add `: Unit =` to explicitly declare `testRandomArrays`'s return type [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/IsolationForestModelWriteReadTest.scala:41: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method overwrite,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/IsolationForestModelWriteReadTest.scala:47: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method extractParamMap,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/IsolationForestModelWriteReadTest.scala:48: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method extractParamMap,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/IsolationForestModelWriteReadTest.scala:67: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method collect,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/IsolationForestModelWriteReadTest.scala:68: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method collect,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/IsolationForestModelWriteReadTest.scala:105: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method overwrite,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/IsolationForestModelWriteReadTest.scala:111: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method extractParamMap,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/IsolationForestModelWriteReadTest.scala:112: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method extractParamMap,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/IsolationForestModelWriteReadTest.scala:131: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method collect,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/IsolationForestModelWriteReadTest.scala:132: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method collect,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/IsolationForestModelWriteReadTest.scala:185: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method overwrite,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/IsolationForestModelWriteReadTest.scala:200: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method collect,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/IsolationForestModelWriteReadTest.scala:201: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method collect,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/IsolationForestModelWriteReadTest.scala:217: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method overwrite,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/IsolationForestModelWriteReadTest.scala:223: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method extractParamMap,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/IsolationForestModelWriteReadTest.scala:224: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method extractParamMap,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/IsolationForestTest.scala:35: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method overwrite,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/IsolationForestTest.scala:40: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method extractParamMap,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/IsolationForestTest.scala:41: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method extractParamMap,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/IsolationForestTest.scala:151: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method collect,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/IsolationForestTest.scala:198: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method count,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/IsolationForestTest.scala:201: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method count,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/TestUtils.scala:31: Auto-application to `()` is deprecated. Supply the empty argument list `()` explicitly to invoke method builder,
or remove the empty argument list from its definition (Java-defined methods are exempt).
In Scala 3, an unapplied method like this will be eta-expanded into a function. [quickfixable]
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/BaggedPointTest.scala:66: method copyArrayToImmutableIndexedSeq in class LowPriorityImplicits2 is deprecated (since 2.13.0): implicit conversions from Array to immutable.IndexedSeq are implemented by copying; use `toIndexedSeq` explicitly if you want to copy, or use the more efficient non-copying ArraySeq.unsafeWrapArray
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/BaggedPointTest.scala:83: method copyArrayToImmutableIndexedSeq in class LowPriorityImplicits2 is deprecated (since 2.13.0): implicit conversions from Array to immutable.IndexedSeq are implemented by copying; use `toIndexedSeq` explicitly if you want to copy, or use the more efficient non-copying ArraySeq.unsafeWrapArray
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/BaggedPointTest.scala:104: method copyArrayToImmutableIndexedSeq in class LowPriorityImplicits2 is deprecated (since 2.13.0): implicit conversions from Array to immutable.IndexedSeq are implemented by copying; use `toIndexedSeq` explicitly if you want to copy, or use the more efficient non-copying ArraySeq.unsafeWrapArray
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/BaggedPointTest.scala:124: method copyArrayToImmutableIndexedSeq in class LowPriorityImplicits2 is deprecated (since 2.13.0): implicit conversions from Array to immutable.IndexedSeq are implemented by copying; use `toIndexedSeq` explicitly if you want to copy, or use the more efficient non-copying ArraySeq.unsafeWrapArray
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/BaggedPointTest.scala:145: method copyArrayToImmutableIndexedSeq in class LowPriorityImplicits2 is deprecated (since 2.13.0): implicit conversions from Array to immutable.IndexedSeq are implemented by copying; use `toIndexedSeq` explicitly if you want to copy, or use the more efficient non-copying ArraySeq.unsafeWrapArray
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/BaggedPointTest.scala:171: method copyArrayToImmutableIndexedSeq in class LowPriorityImplicits2 is deprecated (since 2.13.0): implicit conversions from Array to immutable.IndexedSeq are implemented by copying; use `toIndexedSeq` explicitly if you want to copy, or use the more efficient non-copying ArraySeq.unsafeWrapArray
[Warn] /Users/jv/Documents/git/isolation-forest/isolation-forest/src/test/scala/com/linkedin/relevance/isolationforest/BaggedPointTest.scala:190: method copyArrayToImmutableIndexedSeq in class LowPriorityImplicits2 is deprecated (since 2.13.0): implicit conversions from Array to immutable.IndexedSeq are implemented by copying; use `toIndexedSeq` explicitly if you want to copy, or use the more efficient non-copying ArraySeq.unsafeWrapArray
31 warnings found

BUILD SUCCESSFUL in 1m 39s
12 actionable tasks: 11 executed, 1 up-to-date

And here is the same build after the changes in this PR:

(base) jv@Jamess-MBP isolation-forest % ./gradlew clean build --no-build-cache


> Configure project :
Building version '3.1.1'
  - reason: shipkit-auto-version deduced version based on previous tag: '3.1.0'

> Configure project :isolation-forest
Scala version: 2.13.14
Spark version: 3.5.1

BUILD SUCCESSFUL in 1m 42s
12 actionable tasks: 11 executed, 1 up-to-date

[angie-z]

Thanks a lot for taking care of this repo!