Makes more of test_cuda.py generic and updates test_torch tests (#27135)
Summary:
- Makes more of test_cuda generic, including some serialization tests
- Updates some tests in test_torch to use latest extensibility points and patterns
Most remaining tests in test_cuda.py are either generated (to be moved in a follow-up PR) or deal with CUDA-specific features like streams, events, and querying CUDA devices.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/27135
Differential Revision: D17696478
Pulled By: mruberry
fbshipit-source-id: 51ae424c8a72e725556a2f2bc92ad9a87244b3c0
