Introduce common.WorkingDayTests class

[KJhellico]

Proposed change

Introduce common.WorkingDaysTests class with working days testing methods.

Type of change

• New country/market holidays support (thank you!)
• Supported country/market holidays update (calendar discrepancy fix, localization)
• Existing code/documentation/test/process quality improvement (best practice, cleanup, refactoring, optimization)
• Dependency update (version deprecation/pin/upgrade)
• Bugfix (non-breaking change which fixes an issue)
• Breaking change (a code change causing existing functionality to break)
• New feature (new holidays functionality in general)

Checklist

• I've followed the contributing guidelines
• I've successfully run make check, all checks and tests are green

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (a387595) to head (9e85855).
Report is 2 commits behind head on dev.

Additional details and impacted files

@@            Coverage Diff            @@
##               dev     #2207   +/-   ##
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  Coverage   100.00%   100.00%           
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  Files          195       195           
  Lines        11762     11762           
  Branches      1699      1699           
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  Hits         11762     11762           

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[arkid15r]

Great refactoring, just some naming suggestions:

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[arkid15r]

LGTM

[PPsyrius]

LGTM

We can probably extend this test for remaining countries in the subsequent PRs as well i.e. Russia.