Upgrade mypy to version 0.812 (#55712)
Summary:
Fixes https://github.com/pytorch/pytorch/issues/54211
This was a little more annoying than expected, because the `exclude = ` key in `mypy.ini` is weird. I'll file an upstream issue about that.
I ignored one file, `torch/distributed/elastic/agent/server/api.py` that had ~8 errors that were hard to figure out. This can be done in a follow-up.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/55712
Reviewed By: walterddr
Differential Revision: D27694976
Pulled By: malfet
fbshipit-source-id: 228d8be6af040343ce46595dabaca212e69ccc68
