Update tests/utils/test_nvcodec_utils.py

Co-authored-by: greptile-apps[bot] <165735046+greptile-apps[bot]@users.noreply.github.com>
Signed-off-by: Abhinav Garg <abhinavg@stanford.edu>

Author: abhinavg4

tests/utils/test_nvcodec_utils.py

@@ -797,7 +797,7 @@ def test_generate_decoded_frames_partial_batch(self, mock_cvcuda: Any, mock_torc
 
         # Setup side effect for as_tensor to return different mocks
         def as_tensor_side_effect(*args: Any, **_kwargs: Any) -> Any:
-            if len(args) > 0 and hasattr(args[0], "cuda"):
+            if len(args) == 2 and isinstance(args[1], str):
                 return mock_cvcuda_nhwc
             return mock_cvcuda_tensor