[DataPipe] Count number of successful yields for IterDataPipe (#79657)
This PR adds an attribute and logic to count the number of successful yields from `IterDataPipe`. This information can be useful to fast-forward a DataPipe (or the entire graph) back to a certain state.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/79657
Approved by: https://github.com/VitalyFedyunin
