Add tests for atoms progress bar

[SaidShah]

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

Closes #13

[codecov[bot]]

Codecov Report

Merging #70 into main will increase coverage by 1.74%. The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main      #70      +/-   ##
==========================================
+ Coverage   25.66%   27.41%   +1.74%     
==========================================
  Files          51       51              
  Lines         900      901       +1     
  Branches      209      209              
==========================================
+ Hits          231      247      +16     
+ Misses        662      647      -15     
  Partials        7        7              

Impacted Files	Coverage Δ
src/atoms/progress-bar/progress-bar.tsx	100.00% <100.00%> (+100.00%)	:arrow_up:

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