validate ruby handles multiple indexers endpoints at the same level

[baywet]

more information in #1535

Some APIs might index collections by different ids, historically this can be an issue as we end up generating multiple method in the same class with the same name. We should make sure we de-duplicate the methods when needed.

/repos/{owner}/{repo}/commits/{ref}
/repos/{owner}/{repo}/commits/{commit_sha}

Should result in a GetByRef and a GetByCommitSha method which don't conflict with one another.