Clean up modules' errors

[yito88]

Crate

IBC

Summary

We can clean up some modules' errors

Problem Definition

informalsystems/hermes#1283 (review)

there is an opportunity for more cleanup if we add an Ics03Connection variant to Ics04Error, because that will allow us to reuse errors from Ics03Error (and by extension Ics02Error using the Ics03Error::Ics02Client variant) and avoid redundant errors such as Ics04Error::ClientNotFound, MissingClientState, etc.

Proposal

Ics03Error can reuse Ics02Error, Ics04Error can recues Ics02Error and Ics03Error, and we remove redundant errors

Acceptance Criteria

Redundant errors are cleaned up

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