Add support for bzlmod

[luispadron]

Adds initial support for bzlmod to rules_ios.

Major changes:

• Update versions in repositories.bzl to use minimum supported bzlmod version
• Add MODULE.bazel and required files to enable bzlmod by default in Bazel 6+
• Enable bzlmod by default in the repository

Required workarounds:

• Disable bzlmod when running legacy .xcodeproj tests. This rule collects workspace name in an aspect which now resolves to simply _main in bzlmod. This doesnt seem to cause any actual issues with the generated project besides the repository being named _main. Proper fix is to have this use runfiles but I do not have enough context to make that change.

Things to follow-up on:

• Add bzlmod support for stardoc
  • This requires some more changes to bzl_library usage and update to Stardoc version, will do this in a separate PR before publishing.
• Publish to Bazel Central Registry (and introduce files to required to do so)
• Finalize documentation and update README (after publication)
• Consider better support for legacy xcode project generator, the tests will continue to run without bzlmod as the aspect requires workspace name collection udpates.

Depends on: #716, #719

[luispadron]

Will be blocked by #773 if that merges.

[jerrymarino]

@luispadron I think it's time to land this and forward fix. For the rules_apple 3.x update - I will rebase the changes once we land it.

[justinseanmartin]

FYI - This confused me, because I thought "load_bzlmod_dependencies" means "dependencies that bzlmod needs" rather than "dependencies that bzlmod has already supplied". Just putting this here in case anyone else stumbles across this, and as always, naming is hard.

[luispadron]

I had to update it the other day and I felt the same way lol

Happy to change this to something more clear