Add Forgejo Provider

[DaKingofCheckerz]

This PR adds a provider for Forgejo instances (e.g. Codeberg, the "flagship" instance). Marking as a draft since it hasn't been tested outside of one repo, and since there are some other changes I'd like to look into. Adds a dependency on Forgejo SDK for Go.

TODO:

• Codeberg's docs lists some alternative Forgejo instances, which can be added to auto-detection. Something similar could also be useful for the Gitlab provider.
• Optimization and cleanup. Code was originally copied from the Gitlab provider, and it might still be doing stuff that isn't necessary for Forgejo.
• Misc stuff
  • Look into how the Forgejo SDK handles some of its errors (e.g. an outdated instance, unsupported instance, etc.) and make sure their messages are descriptive.
  • Forgejo has a packages system, which looks similar to some of the stuff in the Gitlab provider. It doesn't look very discoverable via the API, but it might be worth giving a second look

[marcosnils]

hey! thx for the contribution. By any chance do you know if any of the public forgejo repos (https://v12.next.forgejo.org/explore/repos) has attacments so I can test this?

Hopefully we can merge soon 🔜

[DaKingofCheckerz]

hey! thx for the contribution. By any chance do you know if any of the public forgejo repos (https://v12.next.forgejo.org/explore/repos) has attacments so I can test this?

Hopefully we can merge soon 🔜

It doesn't look like there are any on that instance, but here are some that do:

• https://git.disroot.org/Sir_Walrus/Flips (the one I originally tested it with)
• https://codeberg.org/tenacityteam/tenacity
• https://codeberg.org/mergiraf/mergiraf