run cpp tests for non-cuda builds in test_jit.py (#18826)

run cpp tests for non-cuda builds in test_jit.py (#18826)

Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/18826
ghimport-source-id: 7ffa3bc7ef7402a6d6eb6ba5849e197019d77bf8

Stack from [ghstack](https://github.com/ezyang/ghstack):
* **#18826 [jit] run cpp tests for non-cuda builds in test_jit.py**

We did all the work of nicely separating our cpp tests that don't require
CUDA, but they aren't run from test_jit.py if CUDA is missing.

Reviewed By: ZolotukhinM

Differential Revision: D14766287

fbshipit-source-id: 9326b3a5c90f6c20fc8cfaf1a1885a363b91f30a