[improve] Retry re-validating ResourceLock with backoff after errors

[merlimat]

Motivation

The ResourceLock revalidation, after a session expiry, is only getting triggered after the signal of session reconnected. If this is not coming through, there is no further attempt to re-validate and re-acquire the lock.

We should improve the logic to also add timed-based retry logic, with exponential backoff.

Modifications

• Moved Backoff class from pulsar-client -> pulsar-common so that it can be used from pulsar-metadata module.
• Added additional time based logic that triggers revalidation

Verifying this change

• Make sure that the change passes the CI checks.

(Please pick either of the following options)

This change is a trivial rework / code cleanup without any test coverage.

(or)

This change is already covered by existing tests, such as (please describe tests).

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This change added tests and can be verified as follows:

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• Added integration tests for end-to-end deployment with large payloads (10MB)
• Extended integration test for recovery after broker failure

Does this pull request potentially affect one of the following parts:

If the box was checked, please highlight the changes

• Dependencies (add or upgrade a dependency)
• The public API
• The schema
• The default values of configurations
• The threading model
• The binary protocol
• The REST endpoints
• The admin CLI options
• The metrics
• Anything that affects deployment

Documentation

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Matching PR in forked repository

PR in forked repository:

[lhotari]

LGTM