CE upstream

@ayufan Please resolve conflicts:

```
Unmerged paths:
  (use "git add/rm <file>..." as appropriate to mark resolution)

	deleted by them: app/services/create_commit_builds_service.rb
	both modified:   app/services/git_push_service.rb
	both modified:   app/services/git_tag_push_service.rb
	both modified:   spec/models/ci/pipeline_spec.rb
	both modified:   spec/requests/ci/api/builds_spec.rb
```

@ayufan Assigned to you since you are the author https://gitlab.com/gitlab-org/gitlab-ce/commit/39203f1adfc6fee3eca50f0cab99ffc597865200

/cc @jacobvosmaer-gitlab 

See merge request !644