Revert "Fix PHPUnit bool server consts result in null (laravel#5409)" (laravel#5411)

This reverts commit 1c4af33.

Author: GrahamCampbell

phpunit.xml

@@ -26,6 +26,6 @@
         <server name="MAIL_MAILER" value="array"/>
         <server name="QUEUE_CONNECTION" value="sync"/>
         <server name="SESSION_DRIVER" value="array"/>
-        <server name="TELESCOPE_ENABLED" value="(false)"/>
+        <server name="TELESCOPE_ENABLED" value="false"/>
     </php>
 </phpunit>