#558: Developer can style content types output differently per viewport

 - fix BlockRenderSlideItemPosterAppearanceThroughBlockContentTypeTest

Author: petrovsa

app/code/Magento/PageBuilder/Test/Mftf/Test/AdminPageBuilderBlockRenderMediaContentTypesTest/BlockRenderSlideItemPosterAppearanceThroughBlockContentTypeTest.xml

@@ -336,7 +336,7 @@
         <seeElement selector="{{SlideOnFrontend.button('1')}}" stepKey="seeButtonOnHoverCMSPageStorefrontMobile"/>
         <actionGroup ref="ValidateContentTypesStyleEqualsExpectedStyleActionGroup" stepKey="seeOverlayOnHoverCMSPageStorefrontMobile">
             <argument name="selector" value="{{SlideOnFrontend.overlay('1')}}"/>
-            <argument name="expectedProperty" value="{{PageBuilderSlideItemOverlayColor_Blue_Opaque.value}}"/>
+            <argument name="expectedProperty" value="{{PageBuilderSlideItemOverlayColor_Blue_Opaque.rgb}}"/>
             <argument name="cssProperty" value="backgroundColor"/>
         </actionGroup>
         <!-- Validate Slide Link Mobile -->