Add unit test for pkg/archive

[allenxu404]

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Please add a summary of your change

Add unit test for pkg/archive

Does your change fix a particular issue?

Fixes #6338

Please indicate you've done the following:

• Accepted the DCO. Commits without the DCO will delay acceptance.
• Created a changelog file or added /kind changelog-not-required as a comment on this pull request.
• Updated the corresponding documentation in site/content/docs/main.

[codecov-commenter]

Codecov Report

Merging #6396 (41ab949) into main (57bcd8c) will increase coverage by 1.43%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main    #6396      +/-   ##
==========================================
+ Coverage   49.85%   51.28%   +1.43%     
==========================================
  Files         227      228       +1     
  Lines       23376    23777     +401     
==========================================
+ Hits        11653    12194     +541     
+ Misses      10843    10675     -168     
- Partials      880      908      +28     

Impacted Files	Coverage Δ
pkg/archive/extractor.go	54.09% <ø> (+54.09%)	⬆️
pkg/archive/filesystem.go	71.42% <ø> (+28.57%)	⬆️

... and 7 files with indirect coverage changes