Enable usage of async foreach on SF IAsyncEnumerable

[AndreyTretyak]

This change will allow using ServiceFabric.Data.IAsyncEnumerable<T> in the async foreach, since it uses duck typing.
So instead of manually working with enumerator we can write:

async Task SomeMethond(ServiceFabric.Data.IAsyncEnumerable<T> asyncEnumerable)
{
  await foreach(var item in asyncEnumerable)
  {
     /*  Some code that use item variable */
  }
}

This will NOT allow using the extension method of System.Collection.Generic.IAsyncEnumerable<T> like WithCancelation or ConfigureAwait in order to do that interface needs to be implemented.

This change could help with following issue #406

[AndreyTretyak]

@bpm-ms @anmolah @samedder could you please have a look?