I did build a tool for this: https://github.com/mickael-kerjean/filestash. The idea is to link your github repo and let people use it (for example: https://demo.filestash.app/login?next=/files/_posts#type=git...) or create a shared links to make it really easy for anyone to manage the repository without requiring any knowledge of GIT https://demo.filestash.app/s/jekyll