Minor update to README.md

Author: GhaziTriki

README.md

@@ -16,11 +16,11 @@ The official and easy to use **BigBlueButton API for PHP**, makes easy for devel
 [![@bigbluebutton on Twitter](https://img.shields.io/badge/twitter-%40bigbluebutton-blue.svg?style=flat)](https://twitter.com/bigbluebutton)
 ![Website](https://img.shields.io/website-up-down-green-red/http/bigbluebutton.org.svg?label=BigBlueButton.org)
 
-[![PHP 7.1](https://img.shields.io/badge/php-7.1-f33.svg?style=flat-square)](https://php.net/)
-[![PHP 7.2](https://img.shields.io/badge/php-7.2-f33.svg?style=flat-square)](https://php.net/)
-[![PHP 7.3](https://img.shields.io/badge/php-7.3-f93.svg?style=flat-square)](https://php.net/)
-[![PHP 7.4](https://img.shields.io/badge/php-7.4-9c9.svg?style=flat-square)](https://php.net/)
+[![PHP 7.1](https://img.shields.io/badge/php-7.2-f33.svg?style=flat-square)](https://php.net/)
+[![PHP 7.2](https://img.shields.io/badge/php-7.3-f33.svg?style=flat-square)](https://php.net/)
+[![PHP 7.3](https://img.shields.io/badge/php-7.4-f93.svg?style=flat-square)](https://php.net/)
 [![PHP 7.4](https://img.shields.io/badge/php-8.0-9c9.svg?style=flat-square)](https://php.net/)
+[![PHP 7.4](https://img.shields.io/badge/php-8.1-9c9.svg?style=flat-square)](https://php.net/)
 
 ## Installation and usage