[Static Runtime] Refactor fb op tests to use testStaticRuntime (#62064)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/62064
`testStaticRuntime` was previously only available in `test_static_runtime.cc`. It has been moved to a common library `test_utils` to facilitate code re-use. This also lets us test dynamic shapes in `test_fb_operators`
Reviewed By: hlu1
Differential Revision: D29858928
fbshipit-source-id: 68a94760166ddb745972b0f1fc24bed594937d1c