tests: refactor status/stats/pprof/trend api tests

[rleungx]

What problem does this PR solve?

Issue Number: ref #7969.

What is changed and how does it work?

Check List

Tests

• Unit test

Release note

None.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 75.95%. Comparing base (a961ea3) to head (c9f1fd8).
Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #9238      +/-   ##
==========================================
+ Coverage   75.91%   75.95%   +0.03%     
==========================================
  Files         470      470              
  Lines       73103    73103              
==========================================
+ Hits        55497    55524      +27     
+ Misses      14151    14121      -30     
- Partials     3455     3458       +3     

Flag	Coverage Δ
unittests	75.95% <ø> (+0.03%)	⬆️

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[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: lhy1024

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2025-04-23 05:45:01.020640006 +0000 UTC m=+420844.832430387: ☑️ agreed by lhy1024.