[Static Runtime] Make sure the copy version of the op exist in ReplaceWithCopy (#55337)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/55337
`static_runtime::permute_copy` is in fb-only folder. Because `caffe2/test/test_static_runtime.py` is in OSS, we can't load the fb-only operator library. The workaround is to check at runtime whether the op is registered or not.
Test Plan:
This fixed two of the broken tests:
```
✓ Pass: caffe2/test:static_runtime - test_multihead_attention_layer (test_static_runtime.TestStaticModule) (10.316)
✓ Pass: caffe2/test:static_runtime - test_mlp (test_static_runtime.TestStaticModule) (16.134)
```
Reviewed By: ajyu
Differential Revision: D27577066
fbshipit-source-id: ac87dcde71f0d5140ccde448bb49aaebbbb5908a
