Working around Pytorch exporter issue with expand()
WAR changes to prevent issues described in https://nvbugswb.nvidia.com/NvBugs5/SWBug.aspx?bugid=3429305
"ONNX model exported with PyTorch container > 21.06 fails when data of different size is provided to dynamic axes"

Signed-off-by: Boris Fomitchev <bfomitchev@nvidia.com>