Add maximum retry count migration and related logic

Tasklist

• Add maximum retry count column to application settings

• Add new import_status called hard_failed

• Change the status to hard_failed when mirror failed too many times already.

Flow description

• Mirror fails 14+ times in a row
• Gets marked as hard_failed
• Two messages become visible on the project interface requesting action to be taken by the user
• User can either:
  • force the update and retry the cycle again
  • change the import_url which will force an update to happen

Future prospects

• project admins will receive an email requesting action to be taken on the project
• mirror retry count will become adaptive and it will be based on the backoff lower bound which will become configurable instead of a fixed number

Screenshots

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• API support added
• Tests added for this feature/bug
• Review
  • Has been reviewed by UX
  • Has been reviewed by Frontend
  • Has been reviewed by Backend
  • Has been reviewed by Database
• Conform by the merge request performance guides
• Conform by the style guides
• Squashed related commits together

What are the relevant issue numbers?

Closes #2831 and https://gitlab.com/gitlab-org/gitlab-ce/issues/33872