Turn on batched grad testing for non-autogenerated tests in test_nn.py (#50739)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/50739
This does not turn on batched grad testing for autogenerated NewModuleTest
tests and CriterionTest tests. Those are coming later.
Test Plan: - run tests
Reviewed By: ejguan
Differential Revision: D25997677
Pulled By: zou3519
fbshipit-source-id: b4b2d68e0f99c3d573faf237e1e531d0b3fced40
