Warnings when using PHP 8.4

[appreciated]

Make this library compatible with PHP 8.4 without warnings.

I encountered the following warning:

Message: Jsvrcek\ICS\Utility\Provider::__construct(): Implicitly marking parameter $provider as nullable is deprecated, the explicit nullable type must be used instead

[jasvrcek]

@appreciated thanks for flagging this - would you be interested in submitting a pull request with a fix?

[appreciated]

@jasvrcek Thank you for your response. While I usually have no issue with providing a PR, in this specific case, I must decline as I am in the process of transitioning to a new company. As a result this dependency is no longer used by me personally (but still by the company).