Prototype: move Sass-Embedded to optionalDependencies

[acketon]

Description

This PR tests moving sass-embedded to the optionalDependencies. The documentation for webpack/sass-loader state that if you list sass-embedded as an optional dependency it will attempt to use it if it can, but if not, will fall back to using sass (dart-sass in JS). This seems to work in my testing and would let us eliminate the sassCompiler setting and modification of the sass-loader in @wordpress/scripts.

I could use some more help testing this though by using the command time before npm run build, etc. It's not easy to actually know which sass compiler is being used but going off the speed of the build should tell us if it is working. From my testing this works and it's slightly faster if I include sass-embedded in the optionalDependencies vs removing it everywhere.

Sandbox links

You can see my changes in the links below:

• Example 1

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Browser support

I have tested my changes in the following browsers:

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• Chrome
• Firefox
• Safari
• Edge
• IE11

Pre-review checklist for designers and developers

• I have tested my changes in my sandbox and they are working correctly.
• I have tested my changes in the browsers required for my project, and they are working correctly.
• To the best of my knowledge, this code is stable and ready to be deployed to production or staging at any time.
• My code follows BU Coding Standards.

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Information for reviewers

• Related issue, ServiceNow ticket, or Trello card, if applicable
• ActiveCollab project (track time here)
  • This work is non-billable
    
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