Make repo home buttons smaller #3403

There's not much space on that bar (https://github.com/sindresorhus/refined-github/issues/3370) so it might be worth collapsing these buttons <img width="329" alt="" src="https://user-images.githubusercontent.com/1402241/88475310-8d076380-cf26-11ea-9219-8a34227dba77.png">

into

<img width="192" alt="" src="https://user-images.githubusercontent.com/1402241/88475304-8547bf00-cf26-11ea-94be-79fa905f8707.png">