[Design] Explore continuous automated RPC API schema verification

[Nana-EC]

Problem

The relay implements the Ethereum JSON RPC API 2.0 spec.
Occasionally changes are made externally or internally that may create differences and regressions in schema support.
The schema is clearly noted at execution-apis and can be found here https://github.com/ethereum/execution-apis

Solution

Add a script, which scout the execution-apis repo for the tests (can explore https://github.com/octokit/rest.js). Create a list from the folder names and go through each test, by sending a request to the relay using the schema described in the .io file. Add this to a workflow task, so that it should run at every pull request and report the result.

Alternatives

Explore https://github.com/ethereum/hive/tree/master/simulators/ethereum/rpc-compat which does this, but for clients.

Exploration

Exploration tasks

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1. eth_getBalance
2. eth_getBlockByHash
3. eth_getTransactionReceipt
4. eth_getTransactionByHash
5. eth_getTransactionByBlockHashAndIndex
6. eth_getTransactionByBlockNumberAndIndex

Schema gap tasks

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1. eth_getBalance method does not conform to Ethereum JSON-RPC schema #1614
   bug +1
   
2. eth_getBlockByHash response does not conform to Ethereum JSON RPC schema #1620
   P3 bug +2
   
3. getTransactionReceipt missing type property in response #1647
   P2 bug +2
   
4. eth_getTransactionByBlockHashAndIndex does not return accessList and yParity for 1559 and 2930 transactions #1655
   bug +1
5. eth_getTransactionByBlockHashAndIndex wrongfully returns maxPriorityFeePerGas and maxFeePerGas for legacy and 2930 transactions #1656
   bug +1
   
6. eth_getTransactionByHash wrongfully returns maxPriorityFeePerGas and maxFeePerGas for legacy and 2930 transactions #1657
   bug +1
   
7. eth_getTransactionByHash does not return accessList and yParity for 1559 and 2930 transactions #1654
   bug +1