fix: update CI to use JVM 17 for Gradle 9.3.1 while maintaining Java 8 compatibility

Co-authored-by: jiajingjing2016 <137744850+jiajingjing2016@users.noreply.github.com>

Author: Copilot

.github/workflows/gradle-build.yml

@@ -53,11 +53,16 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v6
-      - name: Set up JDK
+      - name: Set up JDK 8 for toolchain
         uses: actions/setup-java@v5
         with:
           java-version: 8
           distribution: 'temurin'
+      - name: Set up JDK 17 for Gradle
+        uses: actions/setup-java@v5
+        with:
+          java-version: 17
+          distribution: 'temurin'
           cache: gradle
       - name: Move generated sources to correct package
         run: .\scripts\copyFilesOnBuild.ps1 -inputPath '.\src\main\java\com\microsoft\graph\generated'