I never bother to track changes on any GitHub repositories, but when I do, I use the Github File Watcher service.

Github File Watcher

Since I rely on many third party, open source, best effort types of solutions, I need a helper service to help me keep track of updates. One nice service I’ve used for some time now allows me keep track of any changes in a specified GitHub repository/file. When setup, it will send an email with a link back to GitHub for me to check what has changed. The nice feature of this is that I can specify which file I want to use as a trigger.

https://app.github-file-watcher.com/