Sort phpunit environment variables alphabetically

phpunit.xml

@@ -26,8 +26,8 @@
         <env name="APP_ENV" value="testing"/>
         <env name="BCRYPT_ROUNDS" value="4"/>
         <env name="CACHE_DRIVER" value="array"/>
-        <env name="SESSION_DRIVER" value="array"/>
-        <env name="QUEUE_CONNECTION" value="sync"/>
         <env name="MAIL_DRIVER" value="array"/>
+        <env name="QUEUE_CONNECTION" value="sync"/>
+        <env name="SESSION_DRIVER" value="array"/>
     </php>
 </phpunit>