It seems that Apple Silicon support has been added in https://github.com/python/cpython/pull/22855, but when I try to build locally I see this error:

```
% ./configure
checking for git... found
checking build system type... Invalid configuration `arm64-apple-darwin20.3.0': machine `arm64-apple' not recognized
configure: error: /bin/sh ./config.sub arm64-apple-darwin20.3.0 failed
```

I went through the `autoreconf` instructions to see if the checked in configure script was outdated, but it doesn't seem to have fixed the issue.

I was able to fix this locally by updating the config.sub and config.guess files (only the former was required but I noticed in previous updates that they were updated in lockstep). I'm a bit wary about that change because it doesn't seem like they are updated frequently (they haven't been in over 3 years), but I will submit it for discussion.