Remove time-based condition for Pull mirroring
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Follow-up for https://gitlab.com/gitlab-org/gitlab/-/issues/216783
### Problem
In Pull Mirroring code we have [a time-based condition](https://gitlab.com/gitlab-org/gitlab/blob/f45304303b3a8dedd2b29235888e326f1f9a0caa/ee/app/workers/update_all_mirrors_worker.rb#L72). We [stopped offering pull mirroring for private projects](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/31217). With the [new deactivation logic for ineligible project mirrors](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/92422) this condition won't be necessary.
### Solution
* Find how many projects are excluded from the query by this condition
* Remove the condition and mark these projects as hard-failed
```
retry_count: 15,
status: "failed",
last_error: "Project mirroring is not supported",
```
issue