fix(dev-bundler): styles loader

[JAdshead]

Provide a general summary of your changes in the Title above.

Description

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For some reason this change was reverted, possibly due to a bad rebase.

This project only accepts pull requests related to open issues.

If suggesting a new feature or change, please discuss it in an issue first.

Motivation

Why is this change required? What issue does it resolve?

See sass/dart-sass#2008

Test Conditions

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How does your change affect the rest of the code.

Types of changes

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• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation (adding or updating documentation)
• Dependency update
• Security update

Checklist

Check boxes that apply:

• My code follows the code style of this project.
• My change requires a change to the documentation and I have updated the documentation accordingly.
• These changes should be applied to a maintenance branch.
• I have added the Apache 2.0 license header to any new files created.