unable to replicate yolov4 onnx conversion example

Bug Report

Which model does this pertain to?

yolov4

Describe the bug

Attempted to replicate results using the steps described in Conversion.ipynb
The result is a much different graph that gives errors when running with the inference.ipynb
It only generates one output of shape: Output shape: [(1, 33, 84)]

Whereas your onnx model has output shape: Output shape: [(1, 52, 52, 3, 85), (1, 26, 26, 3, 85), (1, 13, 13, 3, 85)]
How did you change the output shape?

Reproduction instructions

System Information

OS Platform and Distribution (Linux Ubuntu 18.04):
ONNX version (1.7.0):
Backend/Runtime version (ONNX Runtime 1.5.2):

Provide a code snippet to reproduce your errors.
run the suggested tutorials as written:
https://github.com/onnx/models/blob/master/vision/object_detection_segmentation/yolov4/dependencies/Conversion.ipynb
https://github.com/onnx/models/blob/master/vision/object_detection_segmentation/yolov4/dependencies/inference.ipynb

Start with dependencies/Conversion.ipynb and dependencies/inference.ipynb, then compare the converted graph with the repository's yolov4 model and its reported output shapes. Reproduce the notebooks using the stated ONNX and ONNX Runtime versions; done means the conversion produces the three expected outputs and the inference notebook runs without the reported errors.