PHP8 Warnings

[JonLaliberte]

Deprecated: ctype_digit(): Argument of type int will be interpreted as string in the future in /src/PrintNode/Request.php on line 316

Deprecated: ctype_digit(): Argument of type int will be interpreted as string in the future in /src/PrintNode/Request.php on line 329

[kingIZZZY]

Here's another one

PHP Deprecated: Return type of PrintNode\Entity::jsonSerialize() should either be compatible with JsonSerializable::jsonSerialize(): mixed, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in .../vendor/printnode/printnode-php/src/PrintNode/Entity.php on line 105

Explanation: https://stackoverflow.com/a/71133750
PrintNode's class Entity implements \JsonSerializable: https://www.php.net/manual/en/class.jsonserializable.php
Fix this line with the : mixed at the end of the function signature.