CI: simplify conditional for container image build, use ref name for image tag

.gitlab-ci.yml

@@ -43,16 +43,10 @@ update-docker-image:
           --cache-repo "${CI_REGISTRY_IMAGE}/code-analysis/cache" \
           --dockerfile "${CI_PROJECT_DIR}/docker/code-analysis/Dockerfile" \
           --destination "${CI_REGISTRY_IMAGE}/code-analysis:${CI_COMMIT_SHA}" \
-          --destination "${CI_REGISTRY_IMAGE}/code-analysis:${CI_COMMIT_REF_SLUG}" \
+          --destination "${CI_REGISTRY_IMAGE}/code-analysis:${CI_COMMIT_REF_NAME}" \
           ${IS_DEFAULT_BRANCH:+--destination ${CI_REGISTRY_IMAGE}/code-analysis:latest}
   rules:
-    - if: $CI_PIPELINE_SOURCE == "web" && $REBUILD_DOCKER == "1"
-    - if: '$CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH'
-      changes:
-        - Dockerfile
-        - docker/**
-        - iop
-    - if: '$CI_COMMIT_TAG'
+    - if: '$CI_COMMIT_REF_PROTECTED == "true"'
   interruptible: true
 
 pages: