Do not run valgrind on the Aten unit tests compiled with clang (#37152)
Summary:
Valgrind detects some unitialized variables if torch_cpu is compiled with clang, which are not reproducible if the same code is compiled with gcc nor using address sanitizer tool
See https://github.com/pytorch/pytorch/issues/37117
Pull Request resolved: https://github.com/pytorch/pytorch/pull/37152
Differential Revision: D21241577
Pulled By: malfet
fbshipit-source-id: 4a5dddf2a4fc4238dc9117cb92ee4e34af9e6064
