mcs: make scheduling server test stable

[lhy1024]

What problem does this PR solve?

Issue Number: Close #7362 #7356 #7355 #7338 #7373

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:

• CabinfeverB
• rleungx

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[codecov]

Codecov Report

Merging #7367 (1c408ba) into master (0ebf4b2) will increase coverage by 0.04%.
The diff coverage is 66.66%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #7367      +/-   ##
==========================================
+ Coverage   74.18%   74.23%   +0.04%     
==========================================
  Files         451      451              
  Lines       48877    48886       +9     
==========================================
+ Hits        36261    36289      +28     
+ Misses       9390     9365      -25     
- Partials     3226     3232       +6     

Flag	Coverage Δ
unittests	74.23% <66.66%> (+0.04%)	⬆️

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[CabinfeverB]

/merge

[ti-chi-bot]

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

/run-all-tests

You only need to trigger /merge once, and 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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[ti-chi-bot]

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

Commit hash: e274d1e

[ti-chi-bot]

@lhy1024: Your PR was out of date, I have automatically updated it for you.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

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the ti-community-infra/tichi repository.