[PG Wrapper] Add diff capability (#100214)
Currently we print out the mismatched collectives, but it is hard to
tell exactly the mismatch. This diff adds functionality to detect the exact mismatch
and report it.
New error is as follows:
```
Detected mismatch between collectives on ranks. Rank 0 is running collecti ve: CollectiveFingerPrint(SequenceNumber=1151423632, OpType=ALLREDUCE, TensorShape =[20, 10], TensorDtypes=Float, TensorDeviceTypes=TensorOptions(dtype=float (defaul t), device=cpu, layout=Strided (default), requires_grad=false (default), pinned_me mory=false (default), memory_format=(nullopt))), but Rank 1 is running collective: CollectiveFingerPrint(SequenceNumber=1151423632, OpType=REDUCE, TensorShape=[20, 10], TensorDtypes=Float, TensorDeviceTypes=TensorOptions(dtype=float (default), de vice=cpu, layout=Strided (default), requires_grad=false (default), pinned_memory=f alse (default), memory_format=(nullopt))). Collectives differ in the following aspects: Op type: ALLREDUCEvs REDUCE
```
i.e. the "Collectives differ in the following..." messaging is added.
Differential Revision: [D45375737](https://our.internmc.facebook.com/intern/diff/D45375737/)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/100214
Approved by: https://github.com/H-Huang
