Reference::Commit is based on a documentation error

[flying-sheep]

See github/docs#31914

Despite GitHub’s failure to communicate how they resolved it, the documentation was changed from mentioning “commit sha” as a valid option for ref to not mentioning that, so I assume the only valid options are git refs (refs/heads/..., refs/tags/... and so on)

So I guess Reference::Commit should be deleted, as using it just gives you 404 errors.

[benpueschel]

I was able to replicate this:

    let client = Octocrab::builder().personal_token(TOKEN).build().unwrap();
    let repo = client
        .repos("XAMPPRocky", "octocrab")
        .get_ref(&Reference::Commit(
            "3167540eb0997c998b8ce1cb9aa2fae742011fdf".to_string(),
        ))
        .await
        .expect("Commit reference not valid");

This returns a 404 error, even though the commit sha is valid. Given that the feature doesn't work anyway, this should be safe to remove.