[quant][graphmode][fx][test] Refactor test code for quant-fx2trt unit tests (#67070)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/67070
Test Plan:
python test/test_quantization.py TestQuantizeFxTRTOps
Imported from OSS
Reviewed By: vkuzo
Differential Revision: D31850124
fbshipit-source-id: a314b8869c091743dad7e5a1468985cf8aff6091