[QAT] Auto format the torch/quantization/observer.py` (#57067)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/57067
auto format the code
Test Plan: lint
Reviewed By: jerryzh168
Differential Revision: D27147213
fbshipit-source-id: 008871d276c8891b2411549e17617e5c27d16ee3
