webpack.config.js

 module: {
    rules: [{
        test: /\.scss$/,
        use: [
            'style-loader',
            MiniCssExtractPlugin.loader,
            {
                loader: "css-loader",
                options: {
                    minimize: true,
                    sourceMap: true
                }
            },
            "sass-loader"

        ]
    }]
 }