[DataPipe] Unifying API - removing nesting_level argument from MapperIterDataPipe (#69390)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/69390
As part of the efforts to unify the APIs across different data backends (e.g. TorchData, TorchArrow), we are making changes to different DataPipes' APIs. In this PR, we are removing the input argument `nesting_level` from `MapperIterDataPipe`.
cc VitalyFedyunin ejguan NivekT
Test Plan: Imported from OSS
Reviewed By: ejguan
Differential Revision: D32849465
Pulled By: NivekT
fbshipit-source-id: 963ce70b84a7658331d126e5ed9fdb12273c8e1f
