hmm yes. Trickier then it sounds. Your forever fighting two disconnected streams of information. Github does push out an RSS feed and JSOn data of changes, so you could use that, but you would need a way to find the page in the feed and marry it up with the Kirby page. You would also need to know which Github user = which Kirby user.
I’ve successfully pulled in RSS feed data from a Medium blog into a Kirby site before to display the blog articles, it’s not too hard. It’s kind of a proof of concept, I haven’t polished it off yet, but there some stuff in this thread that should help you out if you went in that direction.