CSS Library: Fix the minify script

[jamigibbs]

Description

In the CSS Library there is a stylesheet minify script that would generate .min.css files like this but now doesn't seem to be working:

Tasks

• Investigate why the minified stylesheets are not updating and fix the script
• Update the package README.md file if needed.

Acceptance Criteria

• The stylesheet minification script works

[caw310]

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