Add script to hide the releases on GitHub's homepage

[saya-rbt]

Hello,

I made this small script to hide the releases on GitHub's homepage. I made my own repo for it here, but then found this repo, so I thought might as well contribute it here 😊

If there's anything bothering you please let me know!

EDIT: I just realized this was a repo for your specific usage, not general Tampermonkey scripts. I keep the PR open in case it might still be useful to you guys, but if not it's fine if you refuse it 😊