Remove deprecated addClassesToCompile call

Hi there,

```
 Symfony\Component\HttpKernel\DependencyInjection\Extension::addClassesToCompile() is deprecated since version 3.3, to be removed in 4.0. 
```

Cheers,

Author: ninsuo

DependencyInjection/EasySecurityExtension.php

@@ -25,11 +25,5 @@ public function load(array $configs, ContainerBuilder $container)
     {
         $loader = new XmlFileLoader($container, new FileLocator(__DIR__.'/../Resources/config'));
         $loader->load('services.xml');
-
-        if (PHP_VERSION_ID < 70000) {
-            $this->addClassesToCompile(array(
-                'EasyCorp\\Bundle\\EasySecurityBundle\\Security\\Security',
-            ));
-        }
     }
 }