#369 Enable Docker push for SHA tag

Pushing a Docker image (even for testing purposes) requires respective
permissions.

Author: ascheman

.github/workflows/gradle-build.yml

@@ -15,7 +15,13 @@ on:
 
 jobs:
   build-artifacts:
+    permissions:
+      packages: write
+      contents: read
     uses: ./.github/workflows/build-artifacts.yml
+    env:
+      DOCKER_USERNAME: ${{ github.repository_owner }}
+      DOCKER_PASSWORD: ${{ secrets.GITHUB_TOKEN }}
     with:
       # SonarQube requires JDK 17 or higher
       java-version: '17'