Fix lint in test_torch.py (#17807)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/17807
Lint also detected a bug in test_linspace where we weren't
actually testing the CUDA case.
Differential Revision: D14388241
fbshipit-source-id: e219e46400f4952c6b384bca3baa0724ef94acde
