Update index.js

index.js

@@ -33,7 +33,7 @@ fileUpload.addEventListener('change', function (e) {
     const reader = new FileReader();
 
     // Set up a callback when the file is loaded
-    reader.onload = function(e2) {
+    reader.onload = (e2) => {
       img = e2.target.result;
       detect();
     }