Update osa6d.md

fixed a bug in the example code

Author: jkaartti

src/content/6/fi/osa6d.md

@@ -148,7 +148,7 @@ const App = () => {
 
   const result = useQuery({
     queryKey: ['notes'],
-    queryFn: () => getNotes // highlight-line
+    queryFn: getNotes // highlight-line
   })
 
   // ...