Re-enable code quality
Gitaly doesn't use GitLabs code quality feature, while it would be nice if the feature matured to the point we could use it.
Items that would need to be resolved:
- Better UX, now the notes are hardly visible.
- Support for multi language repositories (Go, Ruby)
- Customizable rules, if the rules are not the current style it churns the codebase too much
/cc @cdu1