ENGCOM-4088: [Backport] Fixed Issue #20631 Console error on checkout …

…after changing the allowed countries from admin #20885

 - Merge Pull Request #20885 from amol2jcommerce/magento2:2.2-develop-PR-port-20634
 - Merged commits:
   1. 467a2a8
   2. a48a4de
   3. 8d67213
   4. 1a38067

app/code/Magento/Ui/view/base/web/js/form/element/post-code.js

@@ -33,11 +33,11 @@ define([
             }
 
             option = options[value];
-            
+
             if (!option) {
                 return;
             }
-            
+
             if (option['is_zipcode_optional']) {
                 this.error(false);
                 this.validation = _.omit(this.validation, 'required-entry');