filter out commits on forks

Hey, nice project. Love the UI 🔥

I noticed when I clicked on my first commit, it led me to a 404 page. That's when I realized that the repo shown for my first commit was "wrong".

It shows `franceskahoxka` instead of `zero-to-mastery`

Visit [firstcommit.is/takanome-dev](https://firstcommit.is/takanome-dev)