Cache project authorizations even when user has access to zero projects

What does this MR do?

It makes sure that project authorizations are marked as cached even when user has no access to any project. Before this MR we didn't update the cache flag when user has no access to any project which means that we were trying to compute authorizations for this user every time from the beginning.

Does this MR meet the acceptance criteria?

• Changelog entry added
• [ ] Documentation created/updated
• [ ] API support added
• Tests
  • Added for this feature/bug
  • All builds are passing
• Conform by the merge request performance guides
• Conform by the style guides
• Branch has no merge conflicts with master (if it does - rebase it please)
• Squashed related commits together

What are the relevant issue numbers?

Closes #26126 (closed)