Fix test_dispatch.py when running with TORCH_SHOW_CPP_STACKTRACES=1 (#50509)
Summary:
`test_dispatch.py` has many asserts about the error message. When running with `TORCH_SHOW_CPP_STACKTRACES=1`, the error message is different from when `TORCH_SHOW_CPP_STACKTRACES=0`, which makes many tests in `test_dispatch.py` fail. This PR fixes these failures when running with `TORCH_SHOW_CPP_STACKTRACES=1`.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/50509
Reviewed By: ngimel
Differential Revision: D25956853
Pulled By: ezyang
fbshipit-source-id: 3b3696742a7dfb8f52f23a364838ec96945c5662
