tests: fix the testify usage of re.Positive/Negative

[JmPotato]

What problem does this PR solve?

Issue Number: ref #4399.

What is changed and how does it work?

Check List

Tests

• Unit test
• Integration test

Release note

None.

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• rleungx

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 77.45%. Comparing base (5eb66e0) to head (2b9ddab).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #8221      +/-   ##
==========================================
+ Coverage   77.27%   77.45%   +0.17%     
==========================================
  Files         471      471              
  Lines       61317    61317              
==========================================
+ Hits        47385    47494     +109     
+ Misses      10368    10267     -101     
+ Partials     3564     3556       -8     

Flag	Coverage Δ
unittests	77.45% <ø> (+0.17%)	⬆️

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[rleungx]

/merge

[ti-chi-bot]

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[ti-chi-bot]

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

Commit hash: 2b9ddab