add test for webhook/util/convertor

[7h3-3mp7y-m4n]

Ⅰ. Describe what this PR does

• created unit tests for pkg/webhook/util/convertor

Ⅱ. Does this pull request fix one issue?

fixes #2074

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 44.90%. Comparing base (e258de4) to head (20c799c).
⚠️ Report is 35 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2139      +/-   ##
==========================================
+ Coverage   44.81%   44.90%   +0.08%     
==========================================
  Files         318      318              
  Lines       32245    32245              
==========================================
+ Hits        14452    14481      +29     
+ Misses      16372    16342      -30     
- Partials     1421     1422       +1     

Flag	Coverage Δ
unittests	44.90% <ø> (+0.08%)	⬆️

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[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.