Fix attachments error

Author: datashaman

src/Responses/Threads/Messages/ThreadMessageResponse.php

@@ -61,7 +61,7 @@ public static function from(array $attributes, MetaInformation $meta): self
 
         $attachments = array_map(
             fn (array $attachment): ThreadMessageResponseAttachment => ThreadMessageResponseAttachment::from($attachment),
-            $attributes['attachments']
+            $attributes['attachments'] ?? []
         );
 
         return new self(