*: make TestScheduler stable

[rleungx]

What problem does this PR solve?

Issue Number: Close #7062

What is changed and how does it work?

Check List

Tests

• Unit test

Release note

None.

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• lhy1024

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 77.28%. Comparing base (f83feba) to head (ce3a3f4).

❗ Current head ce3a3f4 differs from pull request most recent head aa6fbf6. Consider uploading reports for the commit aa6fbf6 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #8093      +/-   ##
==========================================
- Coverage   77.43%   77.28%   -0.16%     
==========================================
  Files         471      470       -1     
  Lines       61361    61129     -232     
==========================================
- Hits        47513    47241     -272     
- Misses      10281    10324      +43     
+ Partials     3567     3564       -3     

Flag	Coverage Δ
unittests	77.28% <ø> (-0.16%)	⬇️

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[rleungx]

/merge

[ti-chi-bot]

@rleungx: It seems you want to merge this PR, I will help you trigger all the tests:

/run-all-tests

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[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: ce3a3f4

[ti-chi-bot]

@rleungx: Your PR was out of date, I have automatically updated it for you.

If the CI test fails, you just re-trigger the test that failed and the bot will merge the PR for you after the CI passes.

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