finish method
Finish building, and store into the fbBuilder.
Implementation
@override
int finish(fb.Builder fbBuilder) {
  final int? packetOffset =
      _packet == null ? null : fbBuilder.writeListUint8(_packet!);
  final int? typeOffset =
      _type == null ? null : fbBuilder.writeString(_type!);
  fbBuilder.startTable(2);
  fbBuilder.addOffset(0, packetOffset);
  fbBuilder.addOffset(1, typeOffset);
  return fbBuilder.endTable();
}