fix github login on vercel preview deployments

It's probably something I should do but I haven't found a solution so far, so I'm open to get some help :)

When logging in via GitHub App, on the settings I must add a callback URL that will be used to redirect the user after sign in
(see docs: https://docs.github.com/en/apps/creating-github-apps/registering-a-github-app/about-the-user-authorization-callback-url)

This works fine for production and localhost as I specified the two URLs:

But it doesn't work for Vercel's deployment previews as they have different URLs.
I haven't found a way to put wildcards on GitHub or specify a redirect URL that works so... if someone has ideas, let me know! :D