Adding MyPy daemon status file to gitignore (#50132)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/50132
When running mypy command using `dmypy run`, it creates a status file.
This PR adds the file to the ignore list.
Test Plan: Imported from OSS
Reviewed By: samestep
Differential Revision: D25834504
Pulled By: z-a-f
fbshipit-source-id: 6c5a8edd6d8eaf61983e3ca80e798e02d78e38ce
