Reserve refs/replace because `git-replace` is using it

What does this MR do?

Reserve refs/replace because git-replace is using it

Why was this MR needed?

• https://www.kernel.org/pub/software/scm/git/docs/git-replace.html
• https://git-scm.com/book/en/v2/Git-Tools-Replace

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Review
  • Has been reviewed by Backend

What are the relevant issue numbers?

Closes #38234 (closed)