Change return type of jsonSerialize method to be compatible with the internal JsonSerializable::jsonSerialize definition

Author: 7snovic

src/Money.php

@@ -650,7 +650,7 @@ public function toJson($options = 0): string
         return json_encode($this->toArray(), $options);
     }
 
-    public function jsonSerialize(): array
+    public function jsonSerialize(): mixed
     {
         return $this->toArray();
     }