Add `debug_getRawTransaction` method

[natanasow]

Problem

Currently, we're missing some debug_* methods.

Solution

• Implement debug_getRawTransaction method - we should use eth_getTransactionByHash as a base
• Check conformity tests
• Edit openrpc.json and rpc-api.md
• Add tests (if needed)

RPC method:

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "debug_getRawTransaction",
  "params": [
    "0x4c4ef2a33ac952fab10bd9b1433486ee1258c5cb56700f98a9a6f45751db5d19" // transaction hash
  ]
}

Response:

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "0xe6808..." // RLP encoded transaction
}

Note: for not found transactions return "results": "0x"

Alternatives

No response