tests/client: unify http client in tests

[HuSharp]

What problem does this PR solve?

Issue Number: Ref #7969

What is changed and how does it work?

Check List

Tests

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

Release note

None.

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• lhy1024
• nolouch

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[codecov]

Codecov Report

Attention: Patch coverage is 44.11765% with 19 lines in your changes are missing coverage. Please review.

Project coverage is 77.28%. Comparing base (6ded6f8) to head (9c73228).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #8199      +/-   ##
==========================================
- Coverage   77.32%   77.28%   -0.05%     
==========================================
  Files         471      471              
  Lines       61353    61372      +19     
==========================================
- Hits        47442    47432      -10     
- Misses      10349    10378      +29     
  Partials     3562     3562              

Flag	Coverage Δ
unittests	77.28% <44.11%> (-0.05%)	⬇️

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[nolouch]

/merge

[ti-chi-bot]

@nolouch: 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: 9c73228