Add StyleCI badge to the README (#147)

Author: bocharsky-bw

Readme.md

@@ -6,6 +6,8 @@
 [![Quality Score](https://img.shields.io/scrutinizer/g/php-translation/symfony-bundle.svg?style=flat-square)](https://scrutinizer-ci.com/g/php-translation/symfony-bundle)
 [![SensioLabsInsight](https://insight.sensiolabs.com/projects/c289ebe2-41c4-429f-afba-de2f905b9bdb/mini.png)](https://insight.sensiolabs.com/projects/c289ebe2-41c4-429f-afba-de2f905b9bdb)
 [![Total Downloads](https://img.shields.io/packagist/dt/php-translation/symfony-bundle.svg?style=flat-square)](https://packagist.org/packages/php-translation/symfony-bundle)
+[![Coding Style](https://styleci.io/repos/75462210/shield)](https://styleci.io/repos/75462210)
+
 
 **Symfony integration for PHP Translation**