Add tensorrt export tools

[zhiqwang]

Add tools for exporting the TensorRT model from ONNX.

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[codecov]

Codecov Report

Merging #243 (e382738) into main (92dd18e) will decrease coverage by 0.00%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #243      +/-   ##
==========================================
- Coverage   93.62%   93.61%   -0.01%     
==========================================
  Files          11       11              
  Lines         674      673       -1     
==========================================
- Hits          631      630       -1     
  Misses         43       43              

Flag	Coverage Δ
unittests	93.61% <100.00%> (-0.01%)	⬇️

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Impacted Files	Coverage Δ
test/test_runtime.py	100.00% <100.00%> (ø)

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[zhiqwang]

We have some issues on exporting the tensorrt models now, let's fix them in a follow-up PR.