AC-12719: [PageBuilder] MFTF Test Failure - videos playing assertion fails

Remove unwanted character

Author: Sumesh P

app/code/Magento/PageBuilder/Test/Mftf/ActionGroup/BackgroundConfigurationActionGroup/ValidateVideoBackgroundLoadedButNotPlayingAlternateActionGroup.xml

@@ -23,7 +23,7 @@
             <description>Validates that the video in the video background is loaded but not playing.</description>
         </annotations>
         <assertStringNotContainsString stepKey="assertVideoPlaying">
-            <expectedResult type="string">visibility: hidden(</expectedResult>
+            <expectedResult type="string">visibility: hidden</expectedResult>
             <actualResult type="variable">$videoStyle</actualResult>
         </assertStringNotContainsString>
     </actionGroup>