Follow-up from "Add separate form input for user when push or pull mirroring"
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The following discussion from !130334 should be addressed:
- [ ] @vyaklushin started a [discussion](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/130334#note_1559575000):
> **Suggestion** This part partly duplicates `add_mirror` logic. Should we extract it to have a convenient method to setup mirrors?
>
> Something like
>
> ```ruby
> it 'import url has no delimiting colon' do
> add_mirror(url, type: :ssh, direction: :pull)
> ```
issue