Godot 4 project conversion guide

Hey all. I created this guide quite a while ago but it's still relevant! You can use it to convert your Godot 3.x projects to 4.x and it'll help a lot in the transition. For more advanced users, use this: https://gist.github.com/WolfgangSenff/168cb0cbd486c8c9cd507f232165b976

For an actual conversion guide for people just starting to transition to Godot 4, use this: https://gist.github.com/WolfgangSenff/0a9c1d800db42a9a9441b2d0288ed0fd

Feel free to add comments where needed! I'm happy to make updates. I should have posted this pre-LD53, but didn't think to until just now, sorry about that friends!