AC-385: User couldn't upload image through TinyMCE5

- revert stepKey

Author: xmav

app/code/Magento/Cms/Test/Mftf/Test/AdminMediaGalleryPopupUploadImagesWithoutErrorTest.xml

@@ -21,7 +21,7 @@
         <before>
             <!--Enable WYSIWYG options-->
             <comment userInput="Enable WYSIWYG options" stepKey="commentEnableWYSIWYG"/>
-            <actionGroup ref="EnabledWYSIWYGActionGroup" stepKey="enableWYSIWYG"/>
+            <actionGroup ref="EnabledWYSIWYGActionGroup" stepKey="enableWYSIWYGEditor"/>
             <magentoCLI command="config:set cms/wysiwyg/editor 'TinyMCE 4'" stepKey="setValueWYSIWYGEditor"/>
             <!--Create block-->
             <comment userInput="Create block" stepKey="commentCreateBlock"/>