Fix cs with new cs rules (php-cs-fixer version 3.35)

src/Bundle/ChillCalendarBundle/RemoteCalendar/Connector/MSGraph/MSUserAbsenceReaderInterface.php

@@ -18,5 +18,5 @@ interface MSUserAbsenceReaderInterface
     /**
      * @throw UserAbsenceSyncException when the data cannot be reached or is not valid from microsoft
      */
-    public function isUserAbsent(User $user): bool|null;
+    public function isUserAbsent(User $user): null|bool;
 }