Allow Annotated to wrap Final and ClassVar

[GBeauregard]

Pyre Bug

Bug description
The behavior of Annotated has been changed so that it is allowed at runtime to wrap ClassVar and Final. This change helps avoid friction with other users of annotations; see https://bugs.python.org/issue46491 for context. This change has landed in 3.11 and has been backported to 3.9, 3.10, and typing_extensions. pyre should follow suit in allowing the wrapping in order to allow the friction lifting to happen in practice.

Reproduction steps

from typing import Annotated, ClassVar, Final

class C:
    classvar: Annotated[ClassVar[int], (2, 5)] = 4
    const: Annotated[Final[int], "metadata"] = 4

Expected behavior
The above code should type check.

Logs
Please include any relevant logs here:

antest/antest.py:4:4 Incompatible attribute type [8]: Attribute `classvar` declared in class `C` has type `typing.Annotated[ClassVar[int]]` but is used as type `int`.
antest/antest.py:5:4 Incompatible attribute type [8]: Attribute `const` declared in class `C` has type `typing.Annotated[Final[int]]` but is used as type `int`.
antest/antest.py:5:4 Invalid type [31]: Expression `typing.Annotated[Final[int]]` is not a valid type. Final cannot be nested.

Additional context
Client version: 0.9.10
Binary version: d418f5bb10fdee9648eeea3834c8ca56944bd2ce
Corresponding issue for dataclasses (incl InitVar) is at https://bugs.python.org/issue46511
pyright change: microsoft/pyright@8ce7fa6
mypy bug: python/mypy#12061
pytype bug: google/pytype#1110

[stroxler]

Great, thanks @GBeauregard for flagging this!

[yangdanny97]

Seems like this is fixed, the issue no longer repros in the playground

https://pyre-check.org/play?input=from%20typing%20import%20Annotated%2C%20ClassVar%2C%20Final%0A%0Aclass%20C%3A%0A%20%20%20%20classvar%3A%20Annotated%5BClassVar%5Bint%5D%2C%20(2%2C%205)%5D%20%3D%204%0A%20%20%20%20const%3A%20Annotated%5BFinal%5Bint%5D%2C%20%22metadata%22%5D%20%3D%204