perf: use webpack splitChunks defaults (#855)

webpack/client.config.js

@@ -35,10 +35,6 @@ module.exports = {
       terser()
     ],
     splitChunks: {
-      chunks: 'async',
-      minSize: 5000,
-      maxAsyncRequests: Infinity,
-      maxInitialRequests: Infinity,
       name: false // these chunk names can be annoyingly long
     }
   },