Raise a Python exception if a gRPC message surpasses 32mb

[jeffngo]

Plugin developers could potentially need to write a file onto a remote host for certain operations. gRPC sets a default limit of 4MB per message, but that default limit was tuned to 32mb in a recent submission. The problem is that whenever the 32mb limit is reached, the error message that is returned from gRPC/netty is quite cryptic (broken pipe in debug logs).

We want to find a more direct way to communicate that the limit was reached. One idea that was proposed in code review was that we could add a check on the SDK side to check whether or not the 32mb limit will be reached. The problem with this solution is that we do not have a way of querying the Delphix Engine for the tunable without exposing a callback that does that for us.

This feature request is asking for a way to gracefully fail whenever a message/metadata limit is reached from the SDK side.