Docs.rs: Top menu is too narrow for popular crates

[lnicola]

Like tokio:

(the issue count ends up on the next line)

[jyn514]

I think we should just show 'Repository' there instead honestly, the github logo doesn't stand out enough to make it clear that it's a link.

[lnicola]

That works for me, I don't particularly care for those numbers, and if it sidesteps the GitLab integration issue, that's even better.

[jyn514]

Mentoring instructions:

Remove the first {% if %} in https://github.com/rust-lang/docs.rs/blob/df489659d0de9baa5f23896dbc9260a00206f633/templates/rustdoc/topbar.html#L61-L79
so that 'Repository' is shown whether or not this crate is hosted on github.