ACP2E-2086: Admin Panel Slow

- improved required-entry js validation

Author: aplapana

app/code/Magento/PageBuilder/view/adminhtml/web/js/form/element/validator-rules-mixin.js

@@ -234,7 +234,7 @@ define([
                 var allFilled;
 
                 // Validation only for margins and paddings
-                if (typeof value === 'object' && !!(value.padding || value.margin)) {
+                if (value !== null && typeof value === 'object' && !!(value.padding || value.margin)) {
                     allFilled = true;
 
                     _.flatten(_.map(value, _.values)).forEach(function (val) {