[DISCUSS] PIP-363: Add callback parameters to the method: org.apache.pulsar.client.impl.SendCallback.sendComplete.

[Jie crossover]

Hi, Pulsar Community.

I have created a PIP  to add an `OpSendMsgStats` parameter to the
`SendCallback` interface.
This will help us implement `messaging.publish.messages` metric.
PIP link: https://github.com/apache/pulsar/pull/22940
OpenTelemetry Messaging Metrics link:
https://opentelemetry.io/docs/specs/semconv/messaging/messaging-metrics/#metric-messagingpublishduration
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Best Regards！
crossoverJie