Remove unreachable/invalid commits related entries from activity feed
<!--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> - [Close this issue](https://contributors.gitlab.com/manage-issue?action=close&projectId=278964&issueIid=478411) </details> <!--IssueSummary end--> ### Proposal Do not list in the profile activity feed (or delete the activity entries) for the following: - commits that are unreachable or dangling - commits that have invalid hashes (ie: the one where https://gitlab.com/\<username\>/\<project\>/-/commit/\<commit hash\> displays a 404 Git Resource Not Found) _note : this proposal may be extended to any object (blob, tree, branch, etc) that is unreachable or with invalid hash_. _note 2: in case dangling objects may have some uses, we can just consider the ones with invalid hashes_. ### Steps to reproduce 1. create repo 2. make some commits and push 3. introduce a dangling commit and force push 4. run **housekeeping** and **Prune Unreachable Objects** 5. make sure the commit hash return a 404 (using https://gitlab.com/\<username\>/\<project\>/-/commit/\<commit hash\>) 6. go to the profile and still see the entry related to the commit with a now invalid hash @gitlab-bot label ~"user profile"
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