Document BootstrapVue being outdated

Author: srmagura

site/content/docs/5.2/getting-started/javascript.md

@@ -19,7 +19,7 @@ While the Bootstrap CSS can be used with any framework, **the Bootstrap JavaScri
 A better alternative for those using this type of frameworks is to use a framework-specific package **instead of** the Bootstrap JavaScript. Here are some of the most popular options:
 
 - React: [React Bootstrap](https://react-bootstrap.github.io/)
-- Vue: [BootstrapVue](https://bootstrap-vue.org/)
+- Vue: [BootstrapVue](https://bootstrap-vue.org/) (currently only supports Vue 2 and Bootstrap 4)
 - Angular: [ng-bootstrap](https://ng-bootstrap.github.io/)
 
 ## Using Bootstrap as a module