chore: update Realtime API docs to specify public schema tables

web/docs/guides/api.mdx

@@ -273,7 +273,7 @@ alter publication supabase_realtime add table products;
 
 #### Details and links:
 
-- You should only turn on realtime for Public tables (where all data should be accessible). 
+- Realtime only works for tables in the public schema.
 - [JS Reference](/docs/reference/javascript/subscribe): Subscribe to database changes using the realtime client