Fix CI workflow so the Java matrix actually runs.

Un-nest steps from strategy, replace olafurpg/setup-scala with setup-java and setup-sbt, and keep Temurin 17/21.

Author: russwyte

.github/workflows/ci.yaml

@@ -9,26 +9,30 @@ jobs:
     runs-on: ubuntu-latest
 
     strategy:
+      fail-fast: false
       matrix:
-        java-version: [ '17', '21' ]
-
-      steps:
-        - name: Checkout
-          uses: actions/checkout@v4
-
-        - name: Set up JDK & sbt
-          uses: olafurpg/setup-scala@v10
-          with:
-            distribution: 'temurin'
-            java-version: ${{ matrix.java-version }}
-            cache: 'sbt'
-
-        - name: Run scalafmt
-          run: sbt scalafmtCheckAll scalafmtSbtCheck
-
-        - name: Run tests
-          run: sbt test
-          env:
-            AWS_REGION: us-west-2
-            AWS_ACCESS_KEY_ID: ${{ secrets.AWS_ACCESS_KEY_ID }}
-            AWS_SECRET_ACCESS_KEY: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
+        java-version: ['17', '21']
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Set up JDK
+        uses: actions/setup-java@v4
+        with:
+          distribution: temurin
+          java-version: ${{ matrix.java-version }}
+          cache: sbt
+
+      - name: Set up sbt
+        uses: sbt/setup-sbt@v1
+
+      - name: Run scalafmt
+        run: sbt scalafmtCheckAll scalafmtSbtCheck
+
+      - name: Run tests
+        run: sbt test
+        env:
+          AWS_REGION: us-west-2
+          AWS_ACCESS_KEY_ID: ${{ secrets.AWS_ACCESS_KEY_ID }}
+          AWS_SECRET_ACCESS_KEY: ${{ secrets.AWS_SECRET_ACCESS_KEY }}