feat(users): add email to MergeIdentifier object

src/Object/Users/MergeIdentifier.php

@@ -12,16 +12,21 @@ class MergeIdentifier extends BaseObject
 
     public ?UserAlias $user_alias = null;
 
+    public ?string $email = null;
+
+    /** @var ?string[] */
+    public ?array $prioritization = null;
+
     public function validate(bool $strict): void
     {
         parent::validate($strict);
 
-        if (null === $this->external_id && null === $this->user_alias) {
-            throw new ValidationException('One of "external_id" or "user_alias" fields is required');
+        if (null === $this->external_id && null === $this->user_alias && null === $this->email) {
+            throw new ValidationException('One of "external_id", "user_alias" or "email" fields is required');
         }
 
-        if (null !== $this->external_id && null !== $this->user_alias) {
-            throw new ValidationException('Only one of "external_id" and "user_alias" fields must be set');
+        if (\count(\array_filter([$this->external_id, $this->user_alias, $this->email])) > 1) {
+            throw new ValidationException('Only one of "external_id", "user_alias" and "email" fields must be set');
         }
 
         $this->user_alias?->validate($strict);