Add schedule delay for RepositoryUpdateMirrorWorker

What does this MR do and why?

• Contributes to #364799 (closed)
• Feature flag: #365948 (closed)

Problem

RepositoryUpdateMirrorWorker with sticky data consistency cannot find a replica in sync and falls back to primary.

Solution

Schedule RepositoryUpdateMirrorWorker with 1 minute delay. This delay should not be a problem because the delay between projects updates is higher and equal every 30 minutes.

Screenshots or screen recordings

How to set up and validate locally

1. Enable feature flag Feature.enable(:delay_for_repository_update_mirror)
2. Create an empty project
3. Go to Settings -> Repository -> Mirroring repositories
4. Select Mirror direction - Pull, Git repository URL - https://gitlab.com/sinatra/sinatra.git (or any other public git project) and press Mirror repository
5. Open Sidekiq monitoring - http://127.0.0.1:3000/admin/background_jobs (Scheduled tab)
6. You should see RepositoryUpdateMirrorWorker job scheduled with 1 minute delay

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.