Potential fixes to the hacks in #296

[nstarman]

beartype/beartype#682 records issues found in beartype v0.23.rcX.
In #296 we hacked around these issues.
But as beartype/beartype#682 is resolved, there may be a better solution than the #296 hacks.
CC @leycec @PhilipVinc @wesselb.

[leycec]

Down with hacks! @beartype 0.23.0rc1 is (probably) landing tonight, including resolutions for issues plum has been seeing – like:

• typing.Any equality. beartype.door.TypeHint(Any) now compares equal as follows:
  • TypeHint(Any) == TypeHint(Any). Makes sense. 🥴
  • TypeHint(Any) != TypeHint(foo) for all foo != Any. Also makes sense. Probably. 😬
• TypeHint(foo) == TypeHint(bar) now implies hash(TypeHint(foo)) == hash(TypeHint(bar)). Type hints that compare equal now hash equal. Super non-trivial to get that one working, too. You wouldn't believe the things the beartype.door API has seen. 😮‍💨

No one ever said multiple dispatch was gonna be easy. Lemme know if plum needs @beartype to pick any other fruitful issues for it. Thanks to everyone's awesome hard work here, plum is still the juiciest stone fruit.