null given in array_filter()

Problem/Motivation

I am running cim to install this module and to add path prefix to language.

Steps to reproduce

In a database that does not have yet the path prefix enabled, try to install this module.

Proposed resolution

Created patch.

Error: TypeError: array_filter(): Argument #1 ($array) must be of type array, null given in array_filter() (line 113 of /var/www/html/web/modules/contrib/single_language_url_prefix/src/SingleLanguageNegotiationUrl.php.