fix: add sassOptions.outputStyle to expanded in rspack.config.js (#65)

Coming from datavisyn/ordino#1665

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### Summary of changes

- Add solution proposed by
FortAwesome/Font-Awesome#17644 (comment)


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config/rspack.config.js

@@ -333,6 +333,9 @@ module.exports = (webpackEnv, argv) => {
                   loader: 'sass-loader',
                   options: {
                     sourceMap: true, // <-- !!IMPORTANT!!
+                    sassOptions: {
+                      outputStyle: 'expanded', // @see https://github.com/FortAwesome/Font-Awesome/issues/17644#issuecomment-1703318326
+                    },
                   },
                 },
               ],