[issue46348] Morernize `test_typing`

Change by Nikita Sobolev : -- keywords: +patch pull_requests: +28747 stage: -> patch review pull_request: https://github.com/python/cpython/pull/30547 ___ Python tracker ___ _

[issue46348] Morernize `test_typing`

New submission from Nikita Sobolev : There are several very old details in `test_typing`. Some examples: 1. `@skipUnless(sys.version_info >= (3, 3), 'ChainMap was added in 3.3')` https://github.com/python/cpython/blame/dce642f24418c58e67fa31a686575c980c31dd37/Lib/test/test_typing.py#L3583 Pro