Move mypy wrapper to tools (#54268)
Summary:
This PR
- moves `torch/testing/_internal/mypy_wrapper.py` (and its accompanying tests from `test/test_testing.py`) to `tools`,
- removes the now-unused `test_run_mypy` from `test/test_type_hints.py`, and
- replaces the hardcoded list of `mypy` configs (previously duplicated across `mypy_wrapper.py` and `.github/workflows/lint.yml`) with a simpler glob
Pull Request resolved: https://github.com/pytorch/pytorch/pull/54268
Test Plan:
Should also be run in the "Test tools" GHA workflow in CI:
```
python tools/test/test_mypy_wrapper.py
```
Reviewed By: janeyx99
Differential Revision: D27168095
Pulled By: samestep
fbshipit-source-id: a8dc18407b5e4c103ace23a636b0a8534951905a
