Ignore .numpy() under FakeTensorMode() (#120261)

Summary:
Fixes #120259

X-link: pytorch/pytorch#120261
Approved by: https://github.com/jansel

Reviewed By: jeanschmidt

Differential Revision: D54123967

fbshipit-source-id: 1e41321385fc5f8924e26775ddf6a6292c2ad6c6

userbenchmark/dynamo/dynamobench/_dynamo/utils.py

@@ -2013,6 +2013,8 @@ def nnmodule_has_hooks(
 
 def to_numpy_helper(value):
     """Convert tensor and tnp.ndarray to numpy.ndarray."""
+    if is_fake(value):
+        return value
     if isinstance(value, tnp.ndarray):
         return to_numpy_helper(value.tensor)
     elif isinstance(value, torch.Tensor):