Add ignore broadcast tables when unregister storage unit

[jiangML]

Fixes #28910.

Changes proposed in this pull request:

• Add ignore broadcast tables when unregister storage unit
• Fix getInUsedStorageUnitNameAndRulesMap error for RuleMetaData

---

Before committing this PR, I'm sure that I have checked the following options:

• My code follows the code of conduct of this project.
• I have self-reviewed the commit code.
• I have (or in comment I request) added corresponding labels for the pull request.
• I have passed maven check locally : ./mvnw clean install -B -T1C -Dmaven.javadoc.skip -Dmaven.jacoco.skip -e.
• I have made corresponding changes to the documentation.
• I have added corresponding unit tests for my changes.