Added tests for checkbox input

[SaidShah]

• Related GitHub issue(s) linked in PR description
• Destination branch merged, built and tested with your changes
• Code formatted and follows best practices and patterns
• Code builds cleanly (no additional warnings or errors)
• Manually tested
• Automated tests are passing
• No decreases in automated test coverage
• Documentation updated (readme, docs, comments, etc.)
• Localization: No hard-coded error messages in code files (minimally in string constants)
• New component and/ or properties? Make sure to update storybook

Closes #6

[codecov]

Codecov Report

Merging #62 into main will increase coverage by 0.11%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main      #62      +/-   ##
==========================================
+ Coverage   20.62%   20.73%   +0.11%     
==========================================
  Files          51       51              
  Lines         897      897              
  Branches      209      209              
==========================================
+ Hits          185      186       +1     
+ Misses        702      701       -1     
  Partials       10       10              

Impacted Files	Coverage Δ
src/atoms/forms/checkbox-input.tsx	100.00% <100.00%> (+14.28%)	⬆️

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[wintondeshong]

@SaidShah my feedback was minor so feel free to consider my rename and update the PR. Otherwise, good to go from my perspective.

[wintondeshong]

Suggestion: Recommend renaming from isDisabled to isDisabledClassName or something along those lines. While I realize we are in typescript and it would hopefully catch it, isDisabled strongly suggests to readers it is a boolean.

[SaidShah]

Good call, I will change that 👍