Build PRs on Java 17 and 21

.github/workflows/build-pr.yml

@@ -7,15 +7,16 @@ jobs:
     strategy:
       matrix:
         os: [ ubuntu-latest, windows-latest, macos-latest ]
+        jdk: [ 17, 21 ]
     steps:
       - name: Checkout Repository
         uses: actions/checkout@v4
       - name: Validate Gradle Wrapper
         uses: gradle/wrapper-validation-action@v1
-      - name: Setup Java
+      - name: Setup Java ${{ matrix.jdk }}
         uses: actions/setup-java@v4
         with:
           distribution: temurin
-          java-version: 17
+          java-version: ${{ matrix.jdk }}
       - name: Clean Build
         run: ./gradlew clean build