fix: update customFileHeader during tokens build

[adamstankiewicz]

Description

Updates the custom file header auto-generated in output CSS files from the build-tokens NPM script:

• Removes the erroneous "while transforming design tokens" message.
• Updates <root> to <PARAGON_ROOT> as this message is output in custom brand packages, too, which might not define a README.

Old

/**
 * Do not edit directly, this file was auto-generated. while transforming design tokens.
 * See <root>/tokens/README.md for more details.
 */

New

/**
 * Do not edit directly, this file was auto-generated.
 * See <PARAGON_ROOT>/tokens/README.md for more details.
 */

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 93.87%. Comparing base (92c43c3) to head (fc525b7).
Report is 2 commits behind head on release-23.x.

Additional details and impacted files

@@              Coverage Diff              @@
##           release-23.x    #3371   +/-   ##
=============================================
  Coverage         93.87%   93.87%           
=============================================
  Files               232      232           
  Lines              3937     3937           
  Branches            902      929   +27     
=============================================
  Hits               3696     3696           
+ Misses              237      234    -3     
- Partials              4        7    +3     

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[brian-smith-tcril]

[PKulkoRaccoonGang]

Thanks!

[openedx-semantic-release-bot]

🎉 This PR is included in version 23.1.1 🎉

The release is available on:

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

Your semantic-release bot 📦🚀