CircleCI is mostly unviable these days because it severely limits the
number of runs we can do. Since we don't do anything fancy anyway, let's
port to github actions, re-using some of the infrastructure libratbag
already has in place.
We use meson/ninja from pip because building with the latest gives us
some heads-up about upcoming changes. And we're now only building on
ubuntu because that's what's easiest in github. Oh well.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
