fix(dto): fixing dto nullability

Adding in nullability for some DTO objects

Author: awjudd

src/DataTransfer/SubscriberDTO.php

@@ -6,12 +6,12 @@
 
 class SubscriberDTO extends DataTransferObject
 {
-    public string $first_name;
+    public ?string $first_name;
 
-    public string $last_name;
+    public ?string $last_name;
 
     public string $email;
 
     /** @var int[] */
-    public array $tags;
+    public array $tags = [];
 }

src/DataTransfer/SubscriberTagDTO.php

@@ -9,5 +9,5 @@ class SubscriberTagDTO extends DataTransferObject
     /**
      * @var int[]
      */
-    public array $tags;
+    public array $tags = [];
 }

src/DataTransfer/TagDTO.php

@@ -9,5 +9,5 @@ class TagDTO extends DataTransferObject
     public string $name;
 
     /** @var int[] */
-    public array $subscribers;
+    public array $subscribers = [];
 }

src/DataTransfer/TagSubscriberDTO.php

@@ -9,5 +9,5 @@ class TagSubscriberDTO extends DataTransferObject
     /**
      * @var int[]
      */
-    public array $subscribers;
+    public array $subscribers = [];
 }