publishMessageReceived method
Publish message received
Implementation
void publishMessageReceived(MqttMessageReceived event) {
final topic = event.topic;
MqttLogger.log('MqttSubscriptionManager::publishMessageReceived '
'topic is $topic');
final msg = MqttReceivedMessage<MqttMessage>(topic.rawTopic, event.message);
_subscriptionNotifier.add([msg]);
}