Switch important CI from CUDA 9 to 10.1 (#31951)
Summary:
Fixes https://github.com/pytorch/pytorch/issues/31427
Pull Request resolved: https://github.com/pytorch/pytorch/pull/31951
Differential Revision: D19393566
Pulled By: ezyang
fbshipit-source-id: 06f9637791494a453d3fbef765840dc9f9805196
