Update remixicon sprite to v4.9.1

[tvdeyen]

Summary

Updates the vendored remixicon sprite from v3.4.0 (2,496 icons) to v4.9.1 (3,229 icons)

Checklist

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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 (5bea062).
⚠️ Report is 6 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #6438   +/-   ##
=======================================
  Coverage   89.66%   89.66%           
=======================================
  Files         990      990           
  Lines       20792    20792           
=======================================
  Hits        18644    18644           
  Misses       2148     2148           

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