Fixed lint errors

webpack.common.js

@@ -10,7 +10,7 @@ module.exports = {
     output: {
         path: path.resolve(__dirname, 'build'),
         filename: '[name].js',
-        library: "opensheetmusicdisplay"
+        library: 'opensheetmusicdisplay'
     },
     resolve: {
         // Add '.ts' and '.tsx' as a resolvable extension.

webpack.prod.js

@@ -17,7 +17,7 @@ module.exports = merge(common, {
     },
     mode: 'production',
     optimization: {
-        minimize: true,
+        minimize: true
         // splitChunks: {
         //     chunks: 'all',
         //     name: false