Hi everyone, Is MqttIO's checkpointing logic intentional? When MqttIO receives a large number of messages, for example when using a topic with a regular expression like 'data/#'.
It will add these messages to the `MqttCheckpointMark` instance as a list. Then, each time the `MqttCheckpointMark#finalizeCheckpoint` method is executed, it will iterate through the array of messages it has and acknowledge those messages. The problem is that if a large number of messages have already been received before this finalizeCheckpoint is executed, the client will continue to return a null message because no ack has been performed. From the user's point of view, the performance of MqttIO may appear to be poor. Is this the intended behaviour? If so, I think the description of MqttIO should say something about it.
