Defer saving project services to the database if there are no user changes

What does this MR do?

It defers saving project services to the database as long as it is possible. It creates a project service when creating a project only if this project service has an active template. After that project services are saved on the first edit.

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

• tests that used build_missing_services before the change
• number of queries executed

Why was this MR needed?

Motivation in #22281 (closed)

Does this MR meet the acceptance criteria?

• CHANGELOG entry 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?

Fixes #22281 (closed)