Update example/webpack.config.js

Co-authored-by: graphite-app[bot] <96075541+graphite-app[bot]@users.noreply.github.com>

Author: wes-garlock

example/webpack.config.js

@@ -31,7 +31,8 @@ module.exports = {
   },
   plugins: [
     new webpack.DefinePlugin({
-      'process.env.PINWHEEL_API_KEY': JSON.stringify(process.env.PINWHEEL_API_KEY || '')
+      'process.env.PINWHEEL_API_KEY': JSON.stringify(process.env.PINWHEEL_API_KEY || ''),
+      'process.env.PINWHEEL_API_URL': JSON.stringify(process.env.PINWHEEL_API_URL || 'https://sandbox.getpinwheel.com')
     })
   ],
   devServer: {