[why]
The link on the floating Github button explicitely opens the master
branch. We could instead just link to the default branch (which is
technically more correct anyhow).
[how]
Drop branch specification from URL and use default branch.
Signed-off-by: Fini Jastrow <ulf.fini.jastrow@desy.de>
[why]
Keep the dependencies as small as possible.
We already have the github icon in our own set which we import anyhow,
so there is no need to fetch fontawesome's CSS.
[how]
Replace fa-github with nf-fa-github.
Signed-off-by: Fini Jastrow <ulf.fini.jastrow@desy.de>
