Fix PHP Deprecation warnings in PHP8+

[mike-healy]

PHP 8.1 & 8.2 issue some deprecation notices when using Simple Lightbox.
This fixes those warnings without changing functionality.

[bit9labs]

👍 Here for this. Let's fix these bugs instead of saying the solution is to turn off deprecation notices.

[mrgarymartin]

I resolved this with this code:

$ret = parent::add(...func_get_args());

I was coming to see if it was implemented.. but I guess both ways work. Cheers!

[mike-healy]

yes, both seem to work. I don't mind updating my PR to that style.

[mike-healy]

@archetyped do you have a preference, and are you interested in merging this PR?

[digitaldonkey]

I can confirm this being helpful.

But My IDE wants me to change Return type too:

	/**
	 * Add option to collection
	 * @uses SLB_Field_Collection::add() to add item
	 * @param string $id Unique item ID
	 * @param array $properties Item properties
	 * @param bool $update (optional) Should item be updated or overwritten (Default: FALSE)
	 * @return false|object|SLB_Field Option instance
	 */
	function &add( $id, $properties = array(), $update = false ) {
		// Create item
        $ret = parent::add(...func_get_args());
		return $ret;
	}