[quant] Add backward compatiblity test (#36771)
Summary:
re-created the same PR: https://github.com/pytorch/pytorch/pull/36639
because ghimport does not support importing binary files right now
Pull Request resolved: https://github.com/pytorch/pytorch/pull/36771
Test Plan: python test/quantization/test_backward_compatibility.py
Differential Revision: D21080503
Pulled By: jerryzh168
fbshipit-source-id: 1dca08208bccead60bba03e5fb5d39e1a1d7c20d
