Remove Hash-handling code from BitBucket Server UserFinder#uid
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The following discussion from !120931 should be addressed:
- [ ] @.luke started a [discussion](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/120931#note_1396953291):
> **Suggestion (not blocking)**
>
> We could link to the ~"type::maintenance" issue here too (and mention this class in that issue because we might forget to remove the Hash-handling code).
issue