fix(docs): repeated documentation and wrong placement (#6686)

Author: LifeofDan-EL

documentation/tutorial/ui-libraries/authentication/material-ui/react-router/index.md

@@ -15,7 +15,6 @@ Now our application is ready to use with layouts, views and notifications. Only
 - Forgot password page with type `forgotPassword` which renders a forgot password form and works with the `useForgotPassword` hook.
 - Update password page with type `updatePassword` which renders a update password form and works with the `useUpdatePassword` hook.
 
-Now we've refactored our application with Material UI, we only have one thing left to do: handle notifications. Refine triggers notification in various scenarios, such as when a record is created, updated, or deleted, when there is an error from your data provider or your auth provider. It's important to provide feedback to the user when interacting with the application.
 
 ## Using `<AuthPage />` Component
 

documentation/tutorial/ui-libraries/notifications/material-ui/react-router/index.md

@@ -6,10 +6,11 @@ import { Sandpack, AddNotificationProviderToApp } from "./sandpack.tsx";
 
 <Sandpack>
 
-In this step, we will explore integrating Material UI's notification elements with Refine to deliver notifications to users.
+Now we've refactored our application with Material UI, we only have one thing left to do: handle notifications.
 
 Refine triggers notification in various scenarios, such as when a record is created, updated, or deleted, when there is an error from your data provider or your auth provider. It's important to provide feedback to the user when interacting with the application.
 
+
 All these notifications are enabled just by providing a `notificationProvider` prop to the `<Refine />` component. A notification provider is responsible from displaying and dismissing notifications as well as handling undoable mutation notifications.
 
 Material UI provides a `<Snackbar />` component that can be used to display notifications but lacks the built-in ability to manage notifications. To handle the management of notifications, it's recommended to use the `notistack` library, which provides a notification system that can be used to handle these notifications.