Merge branch 'develop' into 'main'

fix: restrict GitLab CI to main branch and drop --provenance flag

See merge request onixbyte/delta-force-guide-server!4

.gitlab-ci.yml

@@ -21,7 +21,6 @@ release:
     - JAR_FILE=$(find build/libs -name '*.jar' | head -1)
     - echo "Building Docker image for tag $CI_COMMIT_TAG with JAR $JAR_FILE"
     - docker build
-        --provenance=false
         -f Dockerfile.ci
         --build-arg JAR_FILE="$JAR_FILE"
         -t "$CI_REGISTRY_IMAGE:$CI_COMMIT_TAG"
@@ -32,4 +31,4 @@ release:
     - docker push "$CI_REGISTRY_IMAGE:$CI_COMMIT_TAG"
     - docker push "$CI_REGISTRY_IMAGE:latest"
   rules:
-    - if: $CI_COMMIT_TAG
+    - if: $CI_COMMIT_TAG && $CI_COMMIT_BRANCH == "main"