[quant][fx] Remove Fuser class in fusion implementation (#73470)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/73470
att, this does not affect user apis since we are only exposing fuse_fx as a public api
Test Plan:
python test/test_quantization.py TestFuseFx
Imported from OSS
Reviewed By: vkuzo
Differential Revision: D34495260
fbshipit-source-id: 3aa253bc7190e50acc7229186f210901ebc5481b
(cherry picked from commit a88517ff6feff7abbece2234d82fd53e33702237)