refs #18034 [finc] inform screen readers about changes in cart

* set aria-live to polite
* set aria-atomic to true

themes/finc/js/cart-finc.js

+/* #18034 - inform screen reader about changes, eventually intregrate by PR into bootstrap cart.js - RL */
+$(document).ready(function() {
+  var cart = document.getElementById("cartSummary");
+  if (cart !== undefined) {
+    cart.setAttribute("aria-live", "polite");
+    cart.setAttribute("aria-atomic", "true");
+  }
+});

themes/finc/theme.config.php

@@ -5,7 +5,8 @@ return [
         'check_item_statuses.js',
         'lightbox_form_cache.js',
         'covers.js',
-        'common-finc.js'
+        'common-finc.js',
+        'cart-finc.js'
     ],
     'helpers' => [
         'aliases' => [