fix: update BaseFee JSON-RPC

[fedekunze]

Description

This PR removes the event filtering logic on the current BaseFee JSON-RPC endpoint.

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[codecov]

Codecov Report

Merging #1059 (42cc265) into main (825d393) will increase coverage by 0.02%.
The diff coverage is 100.00%.

❗ Current head 42cc265 differs from pull request most recent head 77c3e61. Consider uploading reports for the commit 77c3e61 to get more accurate results

@@            Coverage Diff             @@
##             main    #1059      +/-   ##
==========================================
+ Coverage   60.77%   60.79%   +0.02%     
==========================================
  Files          80       80              
  Lines        6666     6670       +4     
==========================================
+ Hits         4051     4055       +4     
  Misses       2404     2404              
  Partials      211      211              

Impacted Files	Coverage Δ
x/feemarket/keeper/eip1559.go	89.83% <100.00%> (+0.73%)	⬆️

[linear]

ENG-193 Base fee is not dynamic

The base fee is not updated correctly and remains static at the value set in x/feemarket.

Example:

❯ curl -X POST --data '{"jsonrpc":"2.0","method":"eth_gasPrice","params":[],"id":73}' -H "Content-Type: application/json" https://eth.bd.evmos.dev:8545

{
  "jsonrpc": "2.0",
  "id": 73,
  "result": "0x7"
}

x/feemarket params pulled from evmos_9000-4:

❯ evmosd query feemarket params --chain-id=evmos_9000-4 --node=https://tendermint.bd.evmos.dev:26657/ --output=json

{
  "params": {
    "no_base_fee": false,
    "base_fee_change_denominator": 8,
    "elasticity_multiplier": 2,
    "enable_height": "0",
    "base_fee": "7"
  }
}

[jolube]

Could you add to the description what the issue is and how it's being addressed?

[fedekunze]

@jolube added a short description. I'll add more details as soon as we add more tests to check the behavior

[crypto-facs]

LGTM