fix classname in website (#2638)

website/pages/en/index.js

@@ -339,7 +339,7 @@ class Index extends React.Component {
       const pageUrl = page => baseUrl + (language ? `${language}/` : '') + page;
 
       return (
-        <div className="productSponsorSection paddingBottom">
+        <div className="productShowcaseSection paddingBottom">
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