Update group validation

assets/javascripts/wizard/initializers/custom.js.es6

@@ -228,6 +228,7 @@ export default {
       'user-selector',
       'text-only',
       'composer',
+      'category',
       'group'
     ];
 
@@ -257,12 +258,10 @@ export default {
           
           if (type === 'checkbox') {
             valid = val;
-          } else if (type === 'category') {
-            valid = val && val.toString().length > 0;
           } else if (type === 'upload') {
             valid = val && val.id > 0;
           } else if (StandardFieldValidation.indexOf(type) > -1) {
-            valid = val && val.length > 0;
+            valid = val && val.toString().length > 0;
           }
         }