Add support for converting sparse bool tensors to dense (#50019)
Summary:
Fixes https://github.com/pytorch/pytorch/issues/49977
Pull Request resolved: https://github.com/pytorch/pytorch/pull/50019
Reviewed By: smessmer
Differential Revision: D25782045
Pulled By: ezyang
fbshipit-source-id: a8389cbecb7e79099292a423a6fd8ac28631905b
