scheduler_test: change scheduler check order

[HuSharp]

What problem does this PR solve?

Issue Number: Close #8612

What is changed and how does it work?

It's better to wait scheduler callback finished.

Check List

Tests

• Unit test
• Manual test (add detailed scripts or steps below)

Release note

None.

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: lhy1024, rleungx

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• OWNERS [lhy1024,rleungx]

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-09-10 07:51:33.479803895 +0000 UTC m=+342763.220227834: ☑️ agreed by rleungx.
• 2024-09-10 07:55:25.137107713 +0000 UTC m=+342994.877531662: ☑️ agreed by lhy1024.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 77.63%. Comparing base (b95ddda) to head (ca7e9fc).
Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #8613      +/-   ##
==========================================
+ Coverage   77.61%   77.63%   +0.02%     
==========================================
  Files         474      474              
  Lines       61891    61891              
==========================================
+ Hits        48035    48050      +15     
+ Misses      10310    10303       -7     
+ Partials     3546     3538       -8     

Flag	Coverage Δ
unittests	77.63% <ø> (+0.02%)	⬆️

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