fix contact request name default value

src/ApiResource/ContactRequest.php

@@ -23,8 +23,8 @@ class ContactRequest
     )]
     protected string $email;
 
-    protected string $name = '';
-    
+    protected ?string $name = null;
+
     #[Assert\Length(
         min: 10,
         minMessage: 'Message must be at least {{ limit }} characters long',