[CHORE] Updated Android related dependencies.

- compileSDK 28 -> 30
- Google Fitness 19.0.0 -> 20.0.0
- Google Auth 18.1.0 -> 19.0.0

Author: dev-juyoung

android/build.gradle

@@ -2,7 +2,7 @@ group 'dev.juyoung.fitness'
 version '1.0-SNAPSHOT'
 
 buildscript {
-    ext.kotlin_version = '1.3.72'
+    ext.kotlin_version = '1.4.21'
     repositories {
         google()
         jcenter()
@@ -25,7 +25,7 @@ apply plugin: 'com.android.library'
 apply plugin: 'kotlin-android'
 
 android {
-    compileSdkVersion 28
+    compileSdkVersion 30
 
     defaultConfig {
         minSdkVersion 23
@@ -54,8 +54,8 @@ dependencies {
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlin_version"
 
     // dependencies for google fit
-    implementation 'com.google.android.gms:play-services-fitness:19.0.0'
-    implementation 'com.google.android.gms:play-services-auth:18.1.0'
+    implementation 'com.google.android.gms:play-services-fitness:20.0.0'
+    implementation 'com.google.android.gms:play-services-auth:19.0.0'
 
     // dependencies for devtools
     implementation 'com.jakewharton.timber:timber:4.7.1'

example/android/app/build.gradle

@@ -26,12 +26,12 @@ apply plugin: 'kotlin-android'
 apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"
 
 android {
-    compileSdkVersion 28
+    compileSdkVersion 30
 
     defaultConfig {
         applicationId "dev.juyoung.fitness_example"
         minSdkVersion 23
-        targetSdkVersion 28
+        targetSdkVersion 30
         versionCode flutterVersionCode.toInteger()
         versionName flutterVersionName
     }

example/android/build.gradle

@@ -1,5 +1,5 @@
 buildscript {
-    ext.kotlin_version = '1.3.72'
+    ext.kotlin_version = '1.4.21'
     repositories {
         google()
         jcenter()