[tensorexpr] Fix promotion of booleans (#43097)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/43097
Boolean arguments weren't promoted, so if you tried to write a comparison with
types such as `Tensor(Bool) == Int` you'd fail typechecking inside the TE
engine.
Test Plan: Imported from OSS
Reviewed By: protonu, zheng-xq
Differential Revision: D23167926
Pulled By: bertmaher
fbshipit-source-id: 47091a815d5ae521637142a5c390e8a51a776906
