docstring only formatting changes: quantize.py, fake_quantize.py, observer.py
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/27415
Reviewed By: zafartahirov
Differential Revision: D17783101
Pulled By: gottbrath
fbshipit-source-id: a7acbc55edfaa75fdbd17fd30d530710a401b22f
