MC-943: Grouping content blocks and containers in the Panel

- simplify afterRender function

Author: anthoula

app/code/Magento/PageBuilder/view/adminhtml/web/template/panel.html

@@ -7,7 +7,7 @@
 
 <div id="pagebuilder-panel-wrapper" class="pagebuilder-panel-wrapper"
     css="visible: isVisible, collapsed: isCollapsed, 'sticky-top': isStickyTop, 'sticky-bottom': isStickyBottom"
-    afterRender="function (element) { afterRender(element); }">
+    afterRender="afterRender">
     <div id="pagebuilder-panel" class="pagebuilder-panel">
         <div class="search-content-types">
             <label for="search-content-types-input"></label>