updateConversationPinnedState method
Implementation
Future<Map<dynamic, dynamic>> updateConversationPinnedState(
    bool isPinned, String conversationID, dynamic conversationType) async {
  final result = await promiseToFuture(ZIM
          .getInstance()!
          .updateConversationPinnedState(
              isPinned, conversationID, conversationType))
      .catchError(_handleError);
  return _jsObjectToMap(result);
}