export_model.py ONNX gives a model that does not work

[enislalmi]

Instructions To Reproduce the 🐛 Bug:

1. Full runnable code or full changes you made:
   No changes.

2. What exact command you run:
   python detectron2/tools/deploy/export_model.py --config-file Detectron2/detectron2/configs/COCO-Detection/retinanet_R_101_FPN_3x.yaml --output ./output --export-method tracing --format onnx --sample-image image_1.bmp MODEL.DEVICE cuda MODEL.WEIGHTS Detectron2/output_object_detection/model_final.pth

3. Full logs or other relevant observations:```
   TracerWarning: Converting a tensor to a Python boolean might cause the trace to be incorrect. We can't record the data flow of Python values, so this value will be treated as a constant in the future. This means that the trace might not generalize to other inputs!
   assert tensor.dim() == 2 and tensor.size(-1) == 4, tensor.size()
   ============= Diagnostic Run torch.onnx.export version 2.0.0+cu117 =============
   verbose: False, log level: Level.ERROR
   ======================= 0 NONE 0 NOTE 0 WARNING 0 ERROR ========================

[01/30 14:29:26 detectron2]: Inputs schema: TupleSchema(schemas=[ListSchema(schemas=[DictSchema(schemas=[IdentitySchema()], sizes=[1], keys=['image'])], sizes=[1])], sizes=[1])
[01/30 14:29:26 detectron2]: Outputs schema: ListSchema(schemas=[DictSchema(schemas=[InstancesSchema(schemas=[TensorWrapSchema(class_name='detectron2.structures.Boxes'), IdentitySchema(), IdentitySchema()], sizes=[1, 1, 1], keys=['pred_boxes', 'pred_classes', 'scores'])], sizes=[4], keys=['instances'])], sizes=[4])
[01/30 14:29:26 detectron2]: Success.

4. please simplify the steps as much as possible so they do not require additional resources to

Expected behavior:

After running the conversion command to ONNX, to have a ONNX that is able to find the same boxes as the .pt does per the same image. The ONNX does not find any boxes.

Environment:

Everything has been done following this:
https://colab.research.google.com/github/mashyko/object_detection/blob/master/Detectron2_Tutorial.ipynb

[enislalmi]

@thiagocrepaldi I also followed your tutorial, pr and open issues, any idea?