[quant][embedding qat] Add basic EmbeddingBag QAT fakeQuant workflow (#65443)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/65443
Test Plan: Imported from OSS
Reviewed By: dagitses, supriyar
Differential Revision: D31456445
Pulled By: b-koopman
fbshipit-source-id: 0edda6e272d9005fce65f2ba6a5e6abc831836de
