Fix TestClusterAccessor test

[junkaixue]

Issues

• My PR addresses the following Helix issues and references them in the PR description:

closed #2749

Description

• Here are some details about my PR, including screenshots of any UI changes:

Set comparison in 11 considered the orders. So add an helper function to do this.

Tests

• The following tests are written for this issue:

• The following is the result of the "mvn test" command on the appropriate module:
  [INFO] Tests run: 226, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 256.424 s - in TestSuite
  [INFO]
  [INFO] Results:
  [INFO]
  [INFO] Tests run: 226, Failures: 0, Errors: 0, Skipped: 0
  [INFO]
  [INFO]
  [INFO] --- jacoco-maven-plugin:0.8.6:report (generate-code-coverage-report) @ helix-rest ---
  [INFO] Loading execution data file /Users/jxue/helix/helix-rest/target/jacoco.exec
  [INFO] Analyzed bundle 'Apache Helix :: Restful Interface' with 95 classes
  [INFO] ------------------------------------------------------------------------
  [INFO] BUILD SUCCESS
  [INFO] ------------------------------------------------------------------------
  [INFO] Total time: 04:22 min
  [INFO] Finished at: 2024-02-26T15:05:04-08:00
  [INFO] ------------------------------------------------------------------------

Changes that Break Backward Compatibility (Optional)

• My PR contains changes that break backward compatibility or previous assumptions for certain methods or API. They include:

(Consider including all behavior changes for public methods or API. Also include these changes in merge description so that other developers are aware of these changes. This allows them to make relevant code changes in feature branches accounting for the new method/API behavior.)

Documentation (Optional)

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Commits

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  1. Subject is separated from body by a blank line
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  4. Subject uses the imperative mood ("add", not "adding")
  5. Body wraps at 72 characters
  6. Body explains "what" and "why", not "how"

Code Quality

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