Update webpack.config.js

examples/closures/webpack.config.js

@@ -10,7 +10,9 @@ module.exports = {
         filename: 'index.js',
     },
     plugins: [
-        new HtmlWebpackPlugin(),
+        new HtmlWebpackPlugin({
+            template: './index.html'
+        }),
         new WasmPackPlugin({
             crateDirectory: path.resolve(__dirname, ".")
         }),