refine apitest to adopt proxy environment

[MinerYang]

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Comprehensive Summary of your change

Issue being fixed

Fixes #(issue)

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• Well Written Title and Summary of the PR
• Label the PR as needed. "release-note/ignore-for-release, release-note/new-feature, release-note/update, release-note/enhancement, release-note/community, release-note/breaking-change, release-note/docs, release-note/infra, release-note/deprecation"
• Accepted the DCO. Commits without the DCO will delay acceptance.
• Made sure tests are passing and test coverage is added if needed.
• Considered the docs impact and opened a new docs issue or PR with docs changes if needed in website repository.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 65.85%. Comparing base (c8c11b4) to head (45ce31c).
⚠️ Report is 613 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff             @@
##             main   #22706       +/-   ##
===========================================
+ Coverage   45.36%   65.85%   +20.49%     
===========================================
  Files         244     1073      +829     
  Lines       13333   116100   +102767     
  Branches     2719     2931      +212     
===========================================
+ Hits         6049    76462    +70413     
- Misses       6983    35395    +28412     
- Partials      301     4243     +3942     

Flag	Coverage Δ
unittests	65.85% <ø> (+20.49%)	⬆️

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see 987 files with indirect coverage changes

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[chlins]

lgtm