Use recursive type aliases in builtins and _typeshed

[AlexWaygood]

Cc. @ilevkivskyi -- is there a risk that this could cause performance regressions for mypy? If so, then it may not be worth it.

[ilevkivskyi]

I think it should be OK. Real problem is big unions, not recursive types per se, recursive types just exaggerate problems with big unions.

[github-actions]

Diff from mypy_primer, showing the effect of this PR on open source code:

discord.py (https://github.com/Rapptz/discord.py)
- discord/ext/commands/converter.py:1177: error: Argument 2 to "issubclass" has incompatible type "_SpecialForm"; expected "Union[type, UnionType, Tuple[Union[type, UnionType, Tuple[Any, ...]], ...]]"  [arg-type]
+ discord/ext/commands/converter.py:1177: error: Argument 2 to "issubclass" has incompatible type "_SpecialForm"; expected "_ClassInfo"  [arg-type]
- discord/ext/commands/hybrid.py:206: error: Argument 2 to "isinstance" has incompatible type "_SpecialForm"; expected "Union[type, UnionType, Tuple[Union[type, UnionType, Tuple[Any, ...]], ...]]"  [arg-type]
+ discord/ext/commands/hybrid.py:206: error: Argument 2 to "isinstance" has incompatible type "_SpecialForm"; expected "_ClassInfo"  [arg-type]

[AlexWaygood]

I think it should be OK. Real problem is big unions, not recursive types per se, recursive types just exaggerate problems with big unions.

I was worried about isinstance()/issubclass(), since they're such fundamental functions :) Thanks for taking a look!

[hauntsaninja]

@ilevkivskyi this PR causes mypy to crash with RecursionError when using --any-exprs-report, want to take a look? python/mypy#14130

[ilevkivskyi]

OK, I can take a look