[fix][broker] Do not try to clean owned bundles from inactive source brokers (ExtensibleLoadManagerImpl only)

[heesung-sn]

Motivation

• Found a bug that the ownership monitor tries to clean owned bundles from inactive source brokers

Modifications

• Fix the bug not to clean owned bundles from inactive source brokers
• Cleaned/refactored override ownership code
• Skip unloading LB internal topics. Instead, close those topics when shutting down the broker.

Verifying this change

• Make sure that the change passes the CI checks.

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

• doc
• doc-required
• doc-not-needed
• doc-complete

Matching PR in forked repository

PR in forked repository: heesung-sn#75

[github-actions]

@heesung-sn Please add the following content to your PR description and select a checkbox:

- [ ] `doc` <!-- Your PR contains doc changes -->
- [ ] `doc-required` <!-- Your PR changes impact docs and you will update later -->
- [ ] `doc-not-needed` <!-- Your PR changes do not impact docs -->
- [ ] `doc-complete` <!-- Docs have been already added -->

[dragosvictor]

Should this not be cherry-picked to 3.1 too?

[heesung-sn]

Should this not be cherry-picked to 3.1 too?

Sure. I can push it there too.