Turn on batched grad testing for CriterionTest (#50744)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/50744
This PR adds a `check_batched_grad=True` option to CriterionTest and
turns it on by default for all CriterionTest-generated tests
Test Plan: - run tests
Reviewed By: ejguan
Differential Revision: D25997676
Pulled By: zou3519
fbshipit-source-id: cc730731e6fae2bddc01bc93800fd0e3de28b32d
