Bugfix: Only filter NULL values on toArray

Resolving issue when trying to reset badge count (badge=0)

Author: rasmuscnielsen

src/Message/PayloadNotification.php

@@ -137,8 +137,10 @@ public function toArray()
         ];
 
         // remove null values
-        $notification = array_filter($notification);
-
+        $notification = array_filter($notification, function($value) {
+            return $value !== null;
+        });
+        
         return $notification;
     }
 }