MAGETWO-91963: Duplicate

- Fixing duplicate stepkey

Author: dhaecker

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

@@ -1255,7 +1255,7 @@
             <argument name="contentBlockType" value="PageBuilderButtonsContentBlock"/>
         </actionGroup>
         <!-- Add 2nd Button Group -->
-        <comment userInput="Add 2nd Button Group" stepKey="commentAddButtonGroup"/>
+        <comment userInput="Add 2nd Button Group" stepKey="commentAddButtonGroup2"/>
         <actionGroup ref="dragContentBlockToStage" stepKey="dragButtonsOntoStage2">
             <argument name="contentBlockType" value="PageBuilderButtonsContentBlock"/>
         </actionGroup>