README: Add "rocket" emoji

Author: pH-7

readme.md

@@ -1,6 +1,6 @@
 # Build a PHP RESTful API
 
-This is the source code of my Udemy course **[Build a Modern REST API with PHP 8.2](https://www.udemy.com/course/build-modern-php-api/)**
+This is the source code of my Udemy course **[Build a Modern REST API with PHP 8.2](https://www.udemy.com/course/build-modern-php-api/)** 🚀
 
 ![Diagram showing example of REST API architecture](example-web-app-REST-API-architecture.svg)