Update npm.gitlab-ci.yml to make CI job fail on error.

lib/gitlab/ci/templates/npm.gitlab-ci.yml

@@ -55,5 +55,5 @@ publish_package:
         npm publish &&
         echo "Successfully published version ${NPM_PACKAGE_VERSION} of ${NPM_PACKAGE_NAME} to GitLab's NPM registry: ${CI_PROJECT_URL}/-/packages"
       } || {
-        echo "No new version of ${NPM_PACKAGE_NAME} published. This is most likely because version ${NPM_PACKAGE_VERSION} already exists in GitLab's NPM registry."
+        echo "No new version of ${NPM_PACKAGE_NAME} published. This is most likely because version ${NPM_PACKAGE_VERSION} already exists in GitLab's NPM registry."; exit 1
       }