change rule in prepare stage

.gitlab-ci.yml

@@ -16,7 +16,7 @@ prepare:index:
   stage: prepare
   rules:
     - if: $CI_COMMIT_BRANCH
-    - if: $CI_MERGE_REQUEST_ID
+    - if: '$CI_PIPELINE_SOURCE == "merge_request_event" && $CI_COMMIT_MESSAGE !~ /tmpBranch/ && $CI_COMMIT_MESSAGE !~ /Update index/'
   script:
     - python .ci/generateIndex.py
     - mkdir .tmp