[docs][quant] Fix FX Graph Mode Quantization tutorial link (#54715)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/54715
Test Plan: Imported from OSS
Reviewed By: vkuzo
Differential Revision: D27338515
fbshipit-source-id: d61b140284548073df42ead1900f179c6ada2f02