Enable Gradient Accumulation fix across all models + trainer fully in forward() (#34283)
* Enable grad accum fix across all models + trainer fully in forward()
* handle peft case
* Account for DDP: need to run scale tests
* Use accelerator state
* Quality
* Guard
* Experiment w/ only fairseq fix
* Fairseq only
* Revert multiply_grads fix
* Mult by grad accum to fully bring back solution
* Style
* Good to go now
* Skip fx tests for now
* Bookmark
* Working now