SubscribeTopicAddSubscribeTick 方法

增加一个订阅的计数信息，不需要手动调用，在 MqttClient 订阅主题之后，会自动增加
Add a subscription count information, no need to manually call it, it will be automatically added after MqttClient subscribes to the topic

public long AddSubscribeTick()

Public Function AddSubscribeTick As Long

public:
long long AddSubscribeTick()

member AddSubscribeTick : unit -> int64