Fix moving local, unhashed upload or pages directories during group transfer

What does this MR do?

Ensures local, unhashed upload or pages directories are moved to their new locations during group transfer.

Are there points in the code the reviewer needs to double check?

Why was this MR needed?

Users see 404s on issue attachments after transferring a group. Also Geo couldn't sync these attachments.

Screenshots (if relevant)

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
• Internationalization required/considered
• End-to-end tests pass (package-qa manual pipeline job)

What are the relevant issue numbers?

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/43993