Implement os.getgrouplist

[kenkoooo]

Implement os.getgrouplist.

Ref #1175

Question

Looks like we don't have test_posix.py to check os.getgrouplist. Do we want to copy it from CPython?

[coolreader18]

Yeah, I think that'd be good! You can follow this blog post to add the unittest file.

[kenkoooo]

Yeah, I think that'd be good! You can follow this blog post to add the unittest file.

Thanks. Let me do that.

[kenkoooo]

@coolreader18 I copied test_posix.py and edited it as the following:

• Put expectedFailure to unimplemented features.
• Put skip to 1 test, which causes panic.
• Put skip to 1 class, which is an unimplemented macOS feature.

And also I formatted bytecode/src/lib.rs and compiler/src/ir.rs to follow the latest rustfmt, but we still need to fix a lot of places to follow the latest clippy. I guess we want to fix them in another PR.

[coolreader18]

Thank you for contributing!