ms: make TestBootstrapDefaultKeyspaceGroup stable

[lhy1024]

What problem does this PR solve?

Issue Number: Close #8395

What is changed and how does it work?

Check List

Tests

• Unit test

Release note

None.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 77.48%. Comparing base (7741924) to head (76fab87).
Report is 3 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #8510      +/-   ##
==========================================
+ Coverage   77.40%   77.48%   +0.07%     
==========================================
  Files         472      472              
  Lines       61800    61829      +29     
==========================================
+ Hits        47838    47907      +69     
+ Misses      10395    10347      -48     
- Partials     3567     3575       +8     

Flag	Coverage Δ
unittests	77.48% <100.00%> (+0.07%)	⬆️

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[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: HuSharp, nolouch

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-08-09 09:27:04.014860797 +0000 UTC m=+603353.881959877: ☑️ agreed by HuSharp.
• 2024-08-09 10:04:15.067955026 +0000 UTC m=+605584.935054114: ☑️ agreed by nolouch.

[ti-chi-bot]

@lhy1024: Your PR was out of date, I have automatically updated it for you.

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[lhy1024]

/test pull-integration-realcluster-test