Add 9.x on requirements.

Author: jaydons

README.md

@@ -11,7 +11,7 @@ This package is a plugin of [Laravel DataTables](https://github.com/yajra/larave
 
 ## Requirements
 - [Laravel 5.4+](https://github.com/laravel/framework)
-- [Laravel DataTables v7.x|v8.x](https://github.com/yajra/laravel-datatables)
+- [Laravel DataTables v7.x|v8.x|9.x](https://github.com/yajra/laravel-datatables)
 
 ## Documentations
 - [Laravel DataTables Documentation](http://yajrabox.com/docs/laravel-datatables)