Multiple instances of the same label can be added to an issue using the API
As seen in gitlab-org/quality/triage-ops#218 (closed), the bot was able to apply the same label twice.
We added some code in https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/25435 to only add unique labels but that seems to not be working here. This may or may not be limited to scoped labels (I didn't test).
Edited by Heinrich Lee Yu