support client upgrade

[rnbguy]

Summary

In case a network has performed a chain upgrade, the relayer needs relay this to counterparty with an upgraded client and consensus state.

Problem Definition

cosmos-sdk chains may perform a software upgrade which needs to be relayed at countryparty.

Proposal

Implement the hermes-sdk components and cosmos-sdk chain specific logic to support ibc client upgrade.

reference:

• client upgrade test at basecoin-rs: https://github.com/informalsystems/basecoin-rs/blob/main/ci/tests/upgrade-client.sh

Acceptance Criteria

• hermes-sdk components
• hermes-sdk impl for cosmos-sdk chain
• ChainBuilder (or something similar) logic to trigger a local chain upgrade.
• e2e tests of cosmos-sdk chains for ibc client upgrade

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