Update CI workflow with more specific Java version

Author: gredler

.github/workflows/gradle-ci-build.yml

@@ -19,7 +19,7 @@ jobs:
       uses: actions/setup-java@v4
       with:
         distribution: 'temurin'
-        java-version: 21
+        java-version: 21.0.7
     - name: Initialize CodeQL
       uses: github/codeql-action/init@v3
       with: