Fix the test TestDelayedWagedRebalanceWithDisabledInstance to avoid skipped test case.

[jiajunwang]

Issues

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

Resolves #1501

Description

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

Fix the test TestDelayedWagedRebalanceWithDisabledInstance to avoid skipped test cases.

Tests

• The following tests are written for this issue:

NA, test change only.

• The following is the result of the "mvn test" command on the appropriate module:

[ERROR] Failures:
[ERROR] TestZkConnectionLost.testLostZkConnection » ThreadTimeout Method org.testng.in...
[INFO]
[ERROR] Tests run: 1236, Failures: 1, Errors: 0, Skipped: 0
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 01:35 h
[INFO] Finished at: 2020-10-30T01:33:05-07:00
[INFO] ------------------------------------------------------------------------

Re-run

[INFO] Tests run: 2, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 505.223 s - in org.apache.helix.integration.TestZkConnectionLost
[INFO]
[INFO] Results:
[INFO]
[INFO] Tests run: 2, Failures: 0, Errors: 0, Skipped: 0
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 08:39 min
[INFO] Finished at: 2020-10-30T10:31:26-07:00
[INFO] ------------------------------------------------------------------------

Documentation (Optional)

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(Link the GitHub wiki you added)

Commits

• My commits all reference appropriate Apache Helix GitHub issues in their subject lines. In addition, my commits follow the guidelines from "How to write a good git commit message":
  1. Subject is separated from body by a blank line
  2. Subject is limited to 50 characters (not including Jira issue reference)
  3. Subject does not end with a period
  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

• My diff has been formatted using helix-style.xml
  (helix-style-intellij.xml if IntelliJ IDE is used)

[jiajunwang]

This PR has been approved by @narendly
I will merge it to master.