Added missing environment definition in console

fixes yiisoft/yii2#10300

Author: cebe

yii

@@ -9,6 +9,7 @@
  */
 
 defined('YII_DEBUG') or define('YII_DEBUG', true);
+defined('YII_ENV') or define('YII_ENV', 'dev');
 
 require(__DIR__ . '/vendor/autoload.php');
 require(__DIR__ . '/vendor/yiisoft/yii2/Yii.php');