Don't use reflection when creating gRPC responses

[robert-zaremba]

Summary

There was a bug in CLI. TL;DR: all requests must go through ABCI. It was solved in #8549

Problem Definition

The current solution is using reflection to construct the response for CLI. This adds an extra roundtrip.

Proposal

Create factory methods to construct the concrete type.
Ref: #8549 (comment)

Alternative approach is to avoid the serialization and wrap the abci.Response: #8549 (comment)

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[tac0turtle]

@robert-zaremba is this still present even though we don't route through tendermint anymore?

[robert-zaremba]

I think this is already solved. Let's also confirm with @AmauryM

[amaury1093]

Yeah I don't think we use reflection in baseapp anymore