withQos method
Sets the Qos of the published message.
Implementation
MqttPublishMessage withQos(MqttQos qos) {
  header!.withQos(qos);
  return this;
}Sets the Qos of the published message.
MqttPublishMessage withQos(MqttQos qos) {
  header!.withQos(qos);
  return this;
}