Create universal macOS build with Intel/M-series chips support.

[marknefedov]

No description provided.

[Zylann]

The build took quite a while, for now I'm suspecting that's simply because the name of the cache changed.
But also the two builds happen in serial. Maybe later something simpler would be to just add an arch parameter to the matrix and executable names (then they will build in parallel), and have another job depending on the first one, which would get both artifacts to generate the universal builds? Tbh I wonder how useful universal builds actually are for nightlies (remember this runs everytime anything is pushed to the repo), though certainly useful to grab them to make a release.

Also do release templates work as univeral builds? I wonder if Godot is actually able to be given such universal binary to export with. I never exported for Mac, but when I look in the Export window Custom Template, it wants a .zip and not a .universal. The artifact is wrapped into a zip by Github, but inside it's one file without extension, although it actually is an archive itself with two files in it. I wonder if that's the same thing Godot wants?

[marknefedov]

Maybe, I'm not sure actually, at least https://docs.godotengine.org/en/stable/contributing/development/compiling/compiling_for_macos.html#building-export-templates show how to make universal binary for templates. Probably need to compose an .app archive.

[Zylann]

I'll assume the universal build is what Godot wants, it might just be a file extension thing. The fact the doc mentions a .app and the export templates window expects .zip is confusing.

I'm still considering multi-architecture and universal builds so I'll likely integrate this to the CI at some point.