Update row-level-security.mdx | correct example (supabase#37361)

Author: TheOtherBrian1

apps/docs/content/guides/database/postgres/row-level-security.mdx

@@ -104,7 +104,7 @@ Let's say you have a table called `profiles` in the public schema and you want t
 -- 1. Create table
 create table profiles (
   id uuid primary key,
-  user_id references auth.users,
+  user_id uuid references auth.users,
   avatar_url text
 );