MC-3852: Update Background Image Implementation on Tabs

- Add page load wait inside test itself as well

Author: davemacaulay

app/code/Magento/PageBuilder/Test/Mftf/Test/AdminPageBuilderTabItemContentTests.xml

@@ -355,6 +355,7 @@
         <!-- Verify Video in Tab on storefront -->
         <comment userInput="View Tab on storefront" stepKey="viewTabOnStorefront"/>
         <amOnPage url="tabs{{PageBuilderPageTitle.pageName}}" stepKey="amOnPageBuilderPage"/>
+        <waitForPageLoad stepKey="waitForPageLoad"/>
         <actionGroup ref="validateVideo" stepKey="validateStorefront">
             <argument name="page" value="VideoOnStorefront"/>
             <argument name="url" value="PageBuilderVideoUrl_YouTube"/>