WIP: Implement storage cleanup worker

What does this MR do?

This implements a cron worker, ideally executed once a day to cleanup:

1. Open multipart uploads,
2. Temporary remote files stored in tmp/cache and tmp/uploads,
3. Temporary local files stored in tmp/cache and tmp/uploads,
4. Temporary empty local folders in tmp/cache and tmp/uploads.

This does not use any DB, it reaches the FS or OS and executes actions against these services.

This code does not use CarrierWave, it uses native FileSystem or Fog API. It is faster and easier to understand.

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Tests added for this feature/bug
• Conform by the code review guidelines
  • Has been reviewed by a Backend maintainer
• Conform by the merge request performance guides
• Conform by the style guides
• If you have multiple commits, please combine them into a few logically organized commits by squashing them
• End-to-end tests pass (package-and-qa manual pipeline job)

What are the relevant issue numbers?

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/47143