Use Case

As a node developer 
I want... (what is the desired change)
So that... (why is the change desired)

User Impact

small to n/a

Dependencies

• We should determine a naming convention for promisified alternatives to callback based functions in the API prior to doing this ticket.  I put an agenda item on tech chat for 6/23

Acceptance Criteria

Create a promisified version of selectServer on the topology.

Refactor the `_processErrorIteratorModeCallback` helper in change streams to be async, and use the async version of selectServer.