Fix `Union[..., NoneType]` injection by `get_type_hints` if a `None` … #1785

Job	Run time
Lint	11s
Run tests (3.8)	6s
Run tests (3.8.0)	13s
Run tests (3.9)	7s
Run tests (3.9.0)	14s
Run tests (3.10)	6s
Run tests (3.10.0)	15s
Run tests (3.11)	7s
Run tests (3.11.0)	13s
Run tests (3.12)	9s
Run tests (3.12.0)	14s
Run tests (3.13)	8s
Run tests (3.13.0)	12s
Run tests (pypy3.8)	9s
Run tests (pypy3.9)	10s
Run tests (pypy3.10)	8s
Create an issue if daily tests failed	0s
	2m 42s

Provide feedback