Update GH Actions JDK version

Author: vnickolov

.github/workflows/gradle_cipr.yml

@@ -18,11 +18,11 @@ jobs:
 
     steps:
       - uses: actions/checkout@v4
-      - name: Set up JDK 17
+      - name: Set up JDK 21
         uses: actions/setup-java@v4
         with:
           distribution: 'temurin'
-          java-version: '17'
+          java-version: '21'
       - name: Grant execute permission for gradlew
         run: chmod +x gradlew
       - name: Run cipr task