Trying to fix GitHub CI workflow

Author: ddekany

.github/workflows/ci.yml

@@ -54,7 +54,7 @@ jobs:
           java-version: 17
           distribution: oracle
       - name: Validate Gradle wrapper
-        uses: gradle/actions/setup-gradle@v6
+        uses: gradle/actions/setup-gradle@4d9f0ba0025fe599b4ebab900eb7f3a1d93ef4c2 # v5.0.0
       - name: Run Build
         id: build_step
         run: './gradlew "-Pfreemarker.signMethod=none" "-Pfreemarker.allowUnsignedReleaseBuild=true" --continue clean build'