Fix typo in the code example in "Introducing Relay Hooks" (#3399)

Summary:
Fix typo in the code example about prefetching data

Pull Request resolved: #3399

Reviewed By: alunyov

Differential Revision: D26980740

Pulled By: poteto

fbshipit-source-id: 81c3280104f88591139acff595c1894b1cd01b70

website-v2/blog/2021-03-09-introducing-relay-hooks.md

@@ -114,7 +114,7 @@ function UserLink({ userId, userName }) {
     {isPopoverVisible && queryReference && (
       <Popover>
         <React.Suspense fallback={<Glimmer />}>
-          <UserPopoverContent queryRef={queryRef} />
+          <UserPopoverContent queryRef={queryReference} />
         </React.Suspense>
       </Popover>
     )}