Surround vars with strings

ci-templates/industrial-ci-templates.yml

@@ -48,7 +48,7 @@
     - docker tag ${DOCKER_ID} ${DOCKER_PUSH_REGISTRY}/${DOCKER_PUSH_NAME}:${CI_COMMIT_SHA}
     - docker push ${DOCKER_PUSH_REGISTRY}/${DOCKER_PUSH_NAME}:${CI_COMMIT_SHA}
     # Tag and push with latest only if it's on the default branch
-    - if [ $CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH ]; then docker tag ${DOCKER_ID} ${DOCKER_PUSH_REGISTRY}/${DOCKER_PUSH_NAME}:latest && docker push ${DOCKER_PUSH_REGISTRY}/${DOCKER_PUSH_NAME}:latest; fi
+    - if [ "$CI_COMMIT_BRANCH" == "$CI_DEFAULT_BRANCH" ]; then docker tag ${DOCKER_ID} ${DOCKER_PUSH_REGISTRY}/${DOCKER_PUSH_NAME}:latest && docker push ${DOCKER_PUSH_REGISTRY}/${DOCKER_PUSH_NAME}:latest; fi
   rules:
     - if: $CI_COMMIT_TAG
       when: always