protected JsonRpcMethods createAdditionalJsonRpcMethodFactory(
      final ProtocolContext protocolContext,
      final ProtocolSchedule protocolSchedule,
      final MiningConfiguration miningConfiguration) {
    return apis -> Collections.emptyMap();
  }
Create additional json rpc method factory json rpc methods.

@param protocolContext the protocol context
@param protocolSchedule the protocol schedule
@param miningConfiguration the mining parameters
@return the json rpc methods
app/src/main/java/org/hyperledger/besu/controller/BesuControllerBuilder.java