Add basic validation of client upgrade proposal contents

[damiannolan]

Summary

We should consider adding an additional validation step of at minimum (chainID suffix, height revision number) before proceeding with client upgrade proposals.

For example, if a client upgrade proposal is submitted which modifies the chainID from testchain-1 to testchain-2, then it is required for the UpgradedClientState provided in the proposal contents to ensure the client state LatestHeight.RevisionNumber follows suit and increments from revision 1 to 2.

The issue arises when a misconfigured upgrade proposal is accepted and a relayer attempts to upgrade the client on the counterparty chain. This results in an error being returned from VerifyUpgradeAndUpdateState when attempting to call Validate on the new client state.

Adding an additional basic validation step to the proposal handler will allow this to be caught much earlier in the client upgrade process.

ref: informalsystems/hermes#3057

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[adizere]

Thank you Damian! This hygienic improvement would likely make diagnosing the problem on the relayer side easier also.

[phamminh0811]

hi @adizere , can I handle this issue?

[crodriguezvega]

hi @adizere , can I handle this issue?

Hi @phamminh0811. Thanks for volunteering! The issue is still labeled with needs discussion so we would like first to iron out some details before anyone starts working on it, so that we prevent re-work. We might have some discussion about it today, so hopefully by the end of the day we can signal that you can start working on it, if you want.

[crodriguezvega]

@phamminh0811 We have decided to close this issue in favour of #1310. However, we can't be work on #1310 yet, since it needs #1282 first.