$filters can be null

Author: brandonkelly

src/records/Webhook.php

@@ -11,7 +11,7 @@
  * @property int|null $groupId
  * @property string $name
  * @property string $class
- * @property string $filters
+ * @property string|null $filters
  * @property string $event
  * @property string $url
  * @property string|null $userAttributes