feat: add amino codec to feeSplit

[hanchon]

Description

Without the amino codec registered we can not send EIP712 transactions, error on submit:

  tx_response: {
    height: '0',
    txhash: '2D17346A4DEEBE9ADA74A06F328DA69BBCC8907623FC910C9D8E9C00AC1FC34D',
    codespace: 'sdk',
    code: 4,
    data: '',
    raw_log: 'signature verification failed; please verify account number (11) and chain-id (evmos_9000-1): failed to pack and hash typedData primary type: there is extra data provided in the message (2 < 4) [evmos/ethermint@v0.19.0/ethereum/eip712/eip712.go:34]: unauthorized',
    logs: [],
    info: '',
    gas_wanted: '3000000',
    gas_used: '84492',
    tx: null,
    timestamp: '',
    events: []
  }
}

Closes: #XXX

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• added a relevant changelog entry to the Unreleased section in CHANGELOG.md
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• written unit and integration tests
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• confirmed the correct type prefix in the PR title
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[linear]

ENG-708 Register Amino codec for feeSplit

Without the amino codec registered, sending a transaction will return:

{
  tx_response: {
    height: '0',
    txhash: '7DC4801161CC1B7CEE86F1BE95FA8105BE3010195409ED76F08E5A30959DDA23',
    codespace: 'sdk',
    code: 2,
    data: '',
    raw_log: 'unable to resolve type URL /feesplit.v1.MsgRegisterFeeSplit: tx parse error',
    logs: [],
    info: '',
    gas_wanted: '0',
    gas_used: '6684',
    tx: null,
    timestamp: '',
    events: []
  }
}

[codecov]

Codecov Report

Merging #859 (b82aab2) into main (4446bcd) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #859      +/-   ##
==========================================
+ Coverage   81.06%   81.07%   +0.01%     
==========================================
  Files         127      127              
  Lines        7244     7251       +7     
==========================================
+ Hits         5872     5879       +7     
  Misses       1231     1231              
  Partials      141      141              

Impacted Files	Coverage Δ
x/feesplit/types/codec.go	100.00% <100.00%> (ø)
x/feesplit/types/msg.go	100.00% <100.00%> (ø)