@Override
  public int hashCode() {
    return Objects.hash(host, udpPort, tcpPort);
  }
If the tcp port is explicitly defined, return it. Otherwise, return the udp port assuming that
the tcp port should match the udp port.

@return The tcp port to use for this endpoint.
ethereum/p2p/src/main/java/org/hyperledger/besu/ethereum/p2p/discovery/Endpoint.java