fix(locale selection): Use international language icon

[tvdeyen]

Summary

The icon for language is not a globe and not flags, because countries are not synomous to spoken languages. Using the language symbol instead.

This allows us to use the globe icon for a timezone select later.

Ref: https://languageicon.org

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 89.66%. Comparing base (1931ee8) to head (4a9d090).
⚠️ Report is 4 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #6439   +/-   ##
=======================================
  Coverage   89.66%   89.66%           
=======================================
  Files         990      990           
  Lines       20792    20792           
=======================================
  Hits        18644    18644           
  Misses       2148     2148           

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