How to use the @automattic/calypso-build/webpack/sass.loader function in @automattic/calypso-build

terserOptions: {
					ecma: 5,
					safari10: true,
					mangle: true,
				},
			} ),
		},
		module: {
			rules: [
				TranspileConfig.loader( {
					workerCount,
					configFile: path.join( __dirname, 'babel.config.js' ),
					cacheDirectory: path.join( __dirname, '.cache' ),
					exclude: /node_modules\//,
				} ),
				SassConfig.loader( {
					preserveCssCustomProperties: false,
					includePaths: [ path.join( __dirname, 'client' ) ],
					prelude: '@import "~@automattic/calypso-color-schemes/src/shared/colors";',
				} ),
				FileConfig.loader(),
			],
		},
		resolve: {
			extensions: [ '.json', '.js', '.jsx' ],
			modules: [ 'node_modules' ],
		},
		node: false,
		plugins: [
			new webpack.DefinePlugin( {
				'process.env.NODE_ENV': JSON.stringify( process.env.NODE_ENV ),
				global: 'window',