fix: eip712 support for pubkey any messages

[hanchon]

Closes: #XXX

Description

Most messages with EIP712 are working fine, but the code is not working if some values that are not the cosmos transaction itself, are contained inside a proto.Any object.

The issue is that when we create read the transactions values, they are parsed using the JSON lib, for example, for public keys it returns the base64 representation of the pubkey as a string.

When the lib generates the types for the EIP712 message, it uses codec.UnpackAny if the message is contained inside a proto.Any object it will return {type:string, value:...} instead of the expected string

For now the only value that I found that is sent as a proto.Any message is the pubkey, but I need to review the rest of the cosmos-sdk messages

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[zmanian]

This PR would close
evmos/evmos#545

[fedekunze]

@zmanian we also would need to remove the single signature check as @tony-iqlusion mentioned

[zmanian]

Iqlusion would be willing to join the validator set with a single sig ledger backed key.

[zmanian]

It's a partial fix for the issue.

[codecov]

Codecov Report

Merging #1076 (03cc04b) into main (d559893) will increase coverage by 0.09%.
The diff coverage is n/a.

❗ Current head 03cc04b differs from pull request most recent head f7ea579. Consider uploading reports for the commit f7ea579 to get more accurate results

@@            Coverage Diff             @@
##             main    #1076      +/-   ##
==========================================
+ Coverage   59.39%   59.49%   +0.09%     
==========================================
  Files          85       84       -1     
  Lines        6992     6940      -52     
==========================================
- Hits         4153     4129      -24     
+ Misses       2622     2598      -24     
+ Partials      217      213       -4     

Impacted Files	Coverage Δ
rpc/types/utils.go	0.00% <0.00%> (ø)
x/evm/client/cli/query.go	0.00% <0.00%> (ø)
x/evm/migrations/v2/migration.go
x/evm/keeper/state_transition.go	75.54% <0.00%> (+0.16%)	⬆️
x/evm/module.go	53.73% <0.00%> (+0.87%)	⬆️
x/evm/types/params.go	100.00% <0.00%> (+6.52%)	⬆️
x/evm/keeper/migrations.go	100.00% <0.00%> (+33.33%)	⬆️

[github-actions]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed in 7 days-before-close if no further activity occurs.

[facs95]

Replaced by this #1283