[FEATURE] Support auto failover in Flink connector

[Lucent-Wong]

Is your feature request related to a problem? Please describe. Currently, to switch the Flink job to the standby Pulsar cluster, it needs to update the job config and start from a former savepoint. With the auto failover feature, I think it can improve the availability of Flink jobs.

Describe the solution you'd like We hope Flink connector of Pulsar can leverage the auto failover feature to improve the availability of Flink jobs.