Fix test failures

Signed-off-by: ajrasane <131806219+ajrasane@users.noreply.github.com>

Author: ajrasane

modelopt/torch/_deploy/utils/torch_onnx.py

@@ -21,10 +21,11 @@
 import os
 import shutil
 import tempfile
-from contextlib import nullcontext
+from contextlib import nullcontext, suppress
 from typing import Any
 
 import onnx
+import onnxconverter_common.float16 as _f16_module
 import torch
 import torch.nn as nn
 from onnx import ModelProto
@@ -58,6 +59,17 @@
 
 from ..utils.onnx_optimizer import Optimizer
 
+# Monkey-patch to fix onnxconverter_common bug where downstream_node is a list
+_original_remove_unnecessary_cast_node = _f16_module.remove_unnecessary_cast_node
+
+
+def _patched_remove_unnecessary_cast_node(graph):
+    with suppress(AttributeError):
+        _original_remove_unnecessary_cast_node(graph)
+
+
+_f16_module.remove_unnecessary_cast_node = _patched_remove_unnecessary_cast_node
+
 ModelMetadata = dict[str, Any]
 ModelType = Any
 ValueInfoType = Any