Don't link LFS-objects multiple times.
What does this MR do?
This makes sure we don't try to link LFS-objects to a project multiple times. This could be the case when destroying a fork with LFS objects.
Does this MR meet the acceptance criteria?
- Changelog entry added, if necessary
- Tests added for this feature/bug
- Has been reviewed by Backend
What are the relevant issue numbers?
Closes #41241 (closed)