Add unit test for ListViewItemStateImageIndexConverter file

[Olina-Zhang]

Related #13442

Proposed changes

• Add unit test file: ListViewItemStateImageIndexConverterTests.cs for ListViewItemStateImageIndexConverter.cs file

Microsoft Reviewers: Open in CodeFlow

[codecov]

Codecov Report

❌ Patch coverage is 86.11111% with 5 lines in your changes missing coverage. Please review.
✅ Project coverage is 76.91036%. Comparing base (2932c39) to head (3abbdf8).
⚠️ Report is 30 commits behind head on main.

Additional details and impacted files

@@                 Coverage Diff                 @@
##                main      #13716         +/-   ##
===================================================
+ Coverage   76.82960%   76.91036%   +0.08075%     
===================================================
  Files           3257        3260          +3     
  Lines         642587      643124        +537     
  Branches       47564       47601         +37     
===================================================
+ Hits          493697      494629        +932     
+ Misses        145229      144832        -397     
- Partials        3661        3663          +2     

Flag	Coverage Δ
Debug	76.91036% <86.11111%> (+0.08075%)	⬆️
integration	18.99069% <ø> (+0.00330%)	⬆️
production	51.58221% <ø> (+0.14070%)	⬆️
test	97.42038% <86.11111%> (+0.00215%)	⬆️
unit	48.97241% <ø> (+0.14598%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[LeafShi1]

LGTM！

[ricardobossan]

Thank you!