Remove `is_variable` from tests (#56305)
Summary:
`is_variable` spits out a deprecation warning during the build (if it's
still something that needs to be tested we can ignore deprecated
warnings for the whole test instead of this change).
Pull Request resolved: https://github.com/pytorch/pytorch/pull/56305
Pulled By: driazati
Reviewed By: ezyang
Differential Revision: D27834218
fbshipit-source-id: c7bbea7e9d8099bac232a3a732a27e4cd7c7b950
Author
davidriazati@fb.com
