[BD-46] fix: grid gutter width var

[khudym]

Description

Add source for grid-gutter-width variable
Issue

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 91.95%. Comparing base (4450782) to head (2ae23fd).
Report is 742 commits behind head on alpha.

Additional details and impacted files

@@           Coverage Diff           @@
##            alpha    #2636   +/-   ##
=======================================
  Coverage   91.95%   91.95%           
=======================================
  Files         216      216           
  Lines        3618     3618           
  Branches      891      891           
=======================================
  Hits         3327     3327           
  Misses        286      286           
  Partials        5        5           

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[edx-semantic-release]

🎉 This PR is included in version 22.0.0-alpha.4 🎉

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[openedx-semantic-release-bot]

🎉 This PR is included in version 23.0.0-alpha.1 🎉

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• npm package (@alpha dist-tag)
• GitHub release

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[openedx-semantic-release-bot]

🎉 This PR is included in version 23.0.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

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