MQE-1069: Migrate Sample Data tests from MTF to MFTF

Author: okolesnyk

app/code/Magento/Catalog/Test/Mftf/ActionGroup/StorefrontAssertProductImagesOnProductPageActionGroup.xml

@@ -10,6 +10,7 @@
         <arguments>
             <argument name="productImage" type="string" defaultValue="Magento_Catalog/images/product/placeholder/image.jpg" />
         </arguments>
+        <waitForElementNotVisible selector="{{StorefrontProductMediaSection.gallerySpinner}}" stepKey="waitGallerySpinnerDisappear" />
         <seeElement selector="{{StorefrontProductMediaSection.gallery}}" stepKey="seeProductGallery" />
         <seeElement selector="{{StorefrontProductMediaSection.productImage(productImage)}}" stepKey="seeProductImage" />
         <click selector="{{StorefrontProductMediaSection.productImage(productImage)}}" stepKey="openFullscreenImage" />

app/code/Magento/Catalog/Test/Mftf/Section/StorefrontProductMediaSection.xml

@@ -9,6 +9,7 @@
 <sections xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:noNamespaceSchemaLocation="urn:magento:mftf:Page/etc/SectionObject.xsd">
     <section name="StorefrontProductMediaSection">
+        <element name="gallerySpinner" type="block" selector="[data-gallery-role='gallery-placeholder'] div.loader>img" />
         <element name="gallery" type="block" selector="[data-gallery-role='gallery']" />
         <element name="productImage" type="text" selector="//*[@data-gallery-role='gallery' and not(contains(@class, 'fullscreen'))]//img[contains(@src, '{{filename}}') and not(contains(@class, 'full'))]" parameterized="true" />
         <element name="productImageFullscreen" type="text" selector="//*[@data-gallery-role='gallery' and contains(@class, 'fullscreen')]//img[contains(@src, '{{filename}}') and contains(@class, 'full')]" parameterized="true" />