[plugin][pulsar] Handle the SendCallback method sign changed.

[dao-jun]

In https://github.com/apache/pulsar/pull/22940, Pulsar will change the org.apache.pulsar.client.impl.SendCallback#sendComplete method sign from

public void sendComplete(Exception e)

to

public void sendComplete(Throwable t, OpSendMsgStats stats)

This PR is to address it.

• [x] Update the CHANGES log.