Add link to Drupal starterkit. (#904)

Co-authored-by: Geoffrey Huntley <[email protected]>

Author: bserem

src/docs/languages/php.md

@@ -11,6 +11,7 @@ Gitpod supports PHP right out of the box, but more advanced features such as deb
 | [symfony-demo](https://github.com/gitpod-io/symfony-demo) | A PHP/Symfony reference application following best practices |[![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/#https://github.com/gitpod-io/symfony-demo) |
 | [magento2gitpod](https://github.com/nemke82/magento2gitpod) | Magento 2 optimized setup for Gitpod: Nginx, MySQL, PHP 7.2, PHP-FPM and more | [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/#https://github.com/nemke82/magento2gitpod) |
 | [koel](https://github.com/phanan/koel) | A personal music streaming server that works | [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/#https://github.com/phanan/koel) |
+| [drupal](github.com/bserem/gitpod-drupal-mysql-starterkit) | Drupal 9 with MySQL, suitable for site building and contrib module development |[![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/#github.com/bserem/gitpod-drupal-mysql-starterkit) |
 
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