504 Timeout should skip to next repo and not crash

[moshloop]

We have a few repo's that have grown quite large and return 504 timeouts when listing the tags, this crashes Tagd, it should rather log a warning, and continue to the next repo.

[nlowe]

That makes sense to me. @moshloop Have you reported the issue to Harbor? We definitely shouldn't be timing out for larger repos.

[lf1029698952]

this is because harbor api perf issue, when list repo tags, will fetch tags all details, but the api fail in a deadlock, harbor api should refactoring And they're already doing it.
goharbor/harbor#6876
I hope before the problem is solved, tagd will skip timeout error and not crash.