Fix APITEST_DB_PROXY_CACHE x509

[YangJiao0817]

Fix APITEST_DB_PROXY_CACHE x509, Because cicd.harbor.vmwarecna uses a self-signed certificate.

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Comprehensive Summary of your change

Issue being fixed

Fixes #(issue)

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[codecov]

Codecov Report

Merging #18977 (b3913cc) into main (b380b78) will increase coverage by 0.02%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main   #18977      +/-   ##
==========================================
+ Coverage   67.42%   67.44%   +0.02%     
==========================================
  Files         993      993              
  Lines      108772   108772              
  Branches     2747     2747              
==========================================
+ Hits        73335    73362      +27     
+ Misses      31499    31477      -22     
+ Partials     3938     3933       -5     

Flag	Coverage Δ
unittests	67.44% <ø> (+0.02%)	⬆️

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see 10 files with indirect coverage changes

[chlins]

lgtm