Update Germany holidays: add East German Uprising Day 2028 in Berlin

[PPsyrius]

Proposed change

Adds the 75th anniversary of the East German uprising of 1953 for Berlin, Germany in 2028. English localization is partially based on a DW article and Ukranian one could use a review here @KJhellico .

Resolves #2089 .

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 run make pre-commit, it didn't generate any changes
• I've run make test, all tests passed locally

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.98%. Comparing base (abcffe3) to head (a3de8e9).
Report is 3 commits behind head on dev.

Additional details and impacted files

@@           Coverage Diff           @@
##              dev    #2092   +/-   ##
=======================================
  Coverage   99.98%   99.98%           
=======================================
  Files         191      191           
  Lines       11537    11537           
  Branches     1738     1738           
=======================================
  Hits        11535    11535           
  Misses          1        1           
  Partials        1        1           

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[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 SonarCloud

[KJhellico]

LGTM. 👍

[arkid15r]

Thanks for addressing this!