chore: add some UT for some pkgs

[csuzhangxc]

What problem does this PR solve?

What is changed and how does it work?

Code changes

• Has Go code change
• Has CI related scripts change

Tests

• Unit test
• E2E test
• Manual test
• No code

Side effects

• Breaking backward compatibility
• Other side effects:

Related changes

• Need to cherry-pick to the release branch
• Need to update the documentation

Release Notes

Please refer to Release Notes Language Style Guide before writing the release note.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 23.29%. Comparing base (56a1888) to head (222d7e5).
Report is 1 commits behind head on feature/v2.

Additional details and impacted files

@@              Coverage Diff               @@
##           feature/v2    #6009      +/-   ##
==============================================
- Coverage       23.69%   23.29%   -0.40%     
==============================================
  Files             152      149       -3     
  Lines           10401     9862     -539     
==============================================
- Hits             2464     2297     -167     
+ Misses           7721     7377     -344     
+ Partials          216      188      -28     

Flag	Coverage Δ
unittest	23.29% <100.00%> (-0.40%)	⬇️

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