Fix marketplace links / remove not released asides

Author: ostenbom

src/content/docs/guides/vercel-integration/index.mdx

@@ -16,6 +16,8 @@ import VercelTestDeploy from "../../../../assets/vercel-test-deploy.png";
   height={500}
 />
 
+[Install Endform from the Vercel Marketplace](https://vercel.com/marketplace/endform).
+
 The Endform Vercel integration helps you to run your Playwright end-to-end
 test suites against your Vercel deployments.