Batching rules for: torch.bmm, torch.dot (#43781)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/43781
Test Plan: - `pytest test/test_vmap.py -v`
Reviewed By: ezyang
Differential Revision: D23400843
Pulled By: zou3519
fbshipit-source-id: a901bba6dc2d8435d314cb4dac85bbd5cd4ee2a5
