Updated README.md

Author: Sammyjo20

.github/README.md

@@ -5,7 +5,7 @@
 This is the Laravel plugin for Saloon, to install it run the following command
 
 ```php
-composer require saloonphp/laravel-plugin "^3.0"
+composer require saloonphp/laravel-plugin "^4.0"
 ```
 >Requires Laravel 9+ and PHP 8.1+