Replaces all the explicit include metadata syntax in the specs (tag:
true) into the implicit one (:tag).
Added a cop to prevent future errors and handle autocorrection.

The helper creates a fork of a project with all provided attributes,
but skipping the creation of the repository on disk.

Closes #38808

Fix https://gitlab.com/gitlab-org/gitlab-ce/issues/38389

Previously the fork button was disabled for all users if they have
exceeded their project limit. This fixes that by changing the check
to see if the user can fork to a group instead of their own namespace.

This behaviour is already possible by visiting the new fork page
directly, so this just fixes the button being disabled.

Closes #38462