Remove `merge_request.project` check in `MergeRequests::BaseService#execute_hooks`
In https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/14886#note_204611783, we added a similar check that is found in CE just to make it similar where the method wouldn't execute if merge_request.project
is nil
.
Knowing that we have a NOT NULL
constraint on target_project_id
and a foreign key constraint to projects
, I think this will never be nil
so we may be able to remove this check.