Adding Deprecation Warning to Vue Router

In this project, you will learn how to add a deprecation warning to the router.addRoutes() method in the vue-router-3.4.9 version. This is an important task as the router.addRoutes() method has been deprecated in Vue Router v3.5.0 and has been removed in Vue Router 4. By adding the deprecation warning, you can help developers using the older version of Vue Router to be aware of the upcoming changes and migrate to the new router.addRoute() method.