PHP Deprecated: Using null as an array offset is deprecated, use an empty string

Have created a pull request which fixes the following warning, which occurs when upgrading to PHP 8.5:

PHP Deprecated: Using null as an array offset is deprecated, use an empty string instead in schema-and-structured-data-for-wp/output/gutenberg.php on line 412

Pull request which fixes this below:

https://github.com/ahmedkaludi/schema-and-structured-data-for-wp/pull/2437

Kind Regards,

Andy