Update constructor to accept nullable Colors parameter

[SMillerDev]

This will resolve issues in PHP 8.4 like the following

PHP Deprecated:  splitbrain\phpcli\Options::__construct(): Implicitly marking parameter $colors as nullable is deprecated, the explicit nullable type must be used instead in phpdraft/vendor/splitbrain/php-cli/src/Options.php on line 43

[SMillerDev]

Thanks for merging it so quickly. I found a couple more after this so I'll make a PR for those later