fix(docs): typo in getting-started/appdir docs (#1038)

Author: notEpsilon

docs/src/app/(docs)/getting-started/appdir/page.mdx

@@ -240,7 +240,7 @@ If using the experimental `ppr` or `dynamicIO` features in Next.js 15, wrap the
 the component.
 
 ```tsx {{title: "app/layout.tsx" }}
-import { connnection } from "next/server"; // [!code ++]
+import { connection } from "next/server"; // [!code ++]
 import { Suspense } from "react"; // [!code ++]
 
 async function UTSSR() {