fix: fix PII test

[JessicaXYWang]

PII test can return a seq of PII. instead of the head, get the one with max confidence for unit test.

[github-actions]

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[JessicaXYWang]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[codecov-commenter]

Codecov Report

Merging #2129 (3cbf7c1) into master (90ded80) will increase coverage by 0.32%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #2129      +/-   ##
==========================================
+ Coverage   85.84%   86.16%   +0.32%     
==========================================
  Files         312      312              
  Lines       16470    16470              
  Branches     1458     1458              
==========================================
+ Hits        14138    14191      +53     
+ Misses       2332     2279      -53     

see 6 files with indirect coverage changes

[mhamilton723]

Thanks! Already fixed this though