Fix tests for 3.10rc1 and up

[Fidget-Spinner]

Before:

======================================================================
FAIL: test_get_type_hints_modules (__main__.GetTypeHintTests)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "...\typing_extensions\src_py3\test_typing_extensions.py", line 473, in test_get_type_hints_modules
    self.assertEqual(gth(ann_module), ann_module_type_hints)
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AssertionError: {1: 2, 'x': <class 'int'>, 'y': <class 'str'>, 'f[39 chars]loat} != {1: 2, 'f': typing.Tuple[int, int], 'x': <class '[21 chars]tr'>}
+ {1: 2, 'f': typing.Tuple[int, int], 'x': <class 'int'>, 'y': <class 'str'>}
- {1: 2,
-  'f': typing.Tuple[int, int],
-  'u': int | float,
-  'x': <class 'int'>,
-  'y': <class 'str'>}

Because ann_module added a new annotation for union tests in 3.10rc1.

[Fidget-Spinner]

@JelleZijlstra in case you were testing locally on 3.10rc1 and wondering why some tests were failing.

This isn't required for release, so we can commit it after 3.10.0.2 is out.

[JelleZijlstra]

Thanks! I'm still running tox locally but it doesn't seem to have gotten past 3.5 yet so I may have to rethink my testing strategy. I will land this so that 3.10 tests pass on the new release.