test: add unit tests for KMP and CertStore controllers

[binbin-li]

Description

What this PR does / why we need it:

Added some unit tests for KMP and CertStore to cover the basic reconcile logics. Check diff at: binbin-li#148

Which issue(s) this PR fixes (optional, using fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when the PR gets merged):

Fixes #

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Helm Chart Change (any edit/addition/update that is necessary for changes merged to the main branch)
• This change requires a documentation update

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Please also list any relevant details for your test configuration

• Test A
• Test B

Checklist:

• Does the affected code have corresponding tests?
• Are the changes documented, not just with inline documentation, but also with conceptual documentation such as an overview of a new feature, or task-based documentation like a tutorial? Consider if this change should be announced on your project blog.
• Does this introduce breaking changes that would require an announcement or bumping the major version?
• Do all new files have appropriate license header?

Post Merge Requirements

• MAINTAINERS: manually trigger the "Publish Package" workflow after merging any PR that indicates Helm Chart Change

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 68.16%. Comparing base (1bd347c) to head (40df15d).
Report is 13 commits behind head on dev.

Additional details and impacted files

@@            Coverage Diff             @@
##              dev    #1439      +/-   ##
==========================================
+ Coverage   66.76%   68.16%   +1.39%     
==========================================
  Files         116      119       +3     
  Lines        6030     6134     +104     
==========================================
+ Hits         4026     4181     +155     
+ Misses       1620     1559      -61     
- Partials      384      394      +10     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[akashsinghal]

Thanks for adding tests!

The merge-base changed after approval.