remove unused env vars

Author: Philipp Kübler

phpunit.xml

@@ -21,10 +21,5 @@
     <php>
         <env name="APP_ENV" value="testing"/>
         <env name="BCRYPT_ROUNDS" value="4"/>
-        <env name="DB_CONNECTION" value="phpunit"/>
-        <env name="CACHE_DRIVER" value="array"/>
-        <env name="SESSION_DRIVER" value="array"/>
-        <env name="QUEUE_CONNECTION" value="sync"/>
-        <env name="MAIL_DRIVER" value="array"/>
     </php>
 </phpunit>