Move test_utils.py back to MYPY (#113745)

Since MYPYNOFOLLOW is about to turn on import following, there's no
reason to keep test_utils.py in the MYPYNOFOLLOW config. Moreover, I'm
not sure it still takes 10 minutes to typecheck this file; adding it to
the MYPY config takes `lintrunner --take MYPY --all-files` from 53s to
57s on my machine, which is substantial but not horrible. I guess we'll
see how it fares on CI.

(Note that we cannot simply merge MYPY and MYPYNOFOLLOW because the
latter config turns on `disallow_any_generics` and so is in that sense
stricter than the MYPY config.)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/113745
Approved by: https://github.com/clee2000

mypy.ini

@@ -37,6 +37,7 @@ files =
     test/test_torch.py,
     test/test_type_hints.py,
     test/test_type_info.py
+    test/test_utils.py
 
 #
 # `exclude` is a regex, not a list of paths like `files` (sigh)