<!--IssueSummary start--> <details> <summary> Everyone can contribute. [Help move this issue forward](https://handbook.gitlab.com/handbook/marketing/developer-relations/contributor-success/community-contributors-workflows/#contributor-links) while earning points, leveling up and collecting rewards. </summary> - [Work on this issue](https://contributors.gitlab.com/manage-issue?action=work&projectId=278964&issueIid=524650) - [Close this issue](https://contributors.gitlab.com/manage-issue?action=close&projectId=278964&issueIid=524650) </details> <!--IssueSummary end--> We already implemented tracking of placeholder reassignment in https://gitlab.com/gitlab-org/gitlab/-/merge_requests/182679 As of %"17.10" placeholders can also be reassigned in [bulk via a CSV file](https://gitlab.com/gitlab-org/gitlab/-/issues/455901) both via the UI and the API. In addition to the tracking events that have been implemented in https://gitlab.com/gitlab-org/gitlab/-/merge_requests/182679 we should also track the `reassignment method` (individual reassignment vs bulk reassignment).