Active callback with contains operator not works with not-array controls

[ArekZw]

Issue description:

Active callback with contains operator not works with not-array (for example with radio-image control).
Code works with Kirki 3.0.9.

From old documentation:
"contains, in : If the context is an array then we’ll check if the value defined exists in the array (using PHP’s in_array() function. If on the other hand the context is a string then we’ll check if the string contains the value defined using PHP’s strpos() and checking not the position of the string but whether the result returns false or not (using === for safety)."

Version used:

3.0.22

Using theme_mods or options?

theme_mods

Code to reproduce the issue (config + field(s))

function my_fields() { 

	Kirki::add_section('general', array(
		'title'       => __('General settings'),
		'description' => __(''),
		'priority'    => 10,
		));

	Kirki::add_field('page_layout', array(
		'type'        => 'radio-image',
		'settings'    => 'page_layout',
		'label'       => esc_attr__('Układ strony-home', 'isb'),
		'section'     => 'general',
		'priority'    => 1,
		'choices'     => array(
			'hor_test1' => admin_url() . '/images/align-right-2x.png',
			'hor_test2' => admin_url() . '/images/align-right-2x.png',
			'hor_test3' => admin_url() . '/images/align-right-2x.png',
			'hor_test4' => admin_url() . '/images/align-right-2x.png',
			'ver_test1' => admin_url() . '/images/align-right-2x.png',
			'ver_test2' => admin_url() . '/images/align-right-2x.png',
			'ver_test3' => admin_url() . '/images/align-right-2x.png'
			),
		));

	Kirki::add_field('header_background_subpage', array(
		'type'        => 'image',
		'settings'    => 'header_background_subpage',
		'label'       => __('Header background subpage', 'isb'),
		'section'     => 'general',
		'default'     => 'http://loremflickr.com/1280/450',
		'priority'    => 10,
		'active_callback'    => array(
			array(
				'setting'  => 'page_layout',
				'operator' => 'contains',
				'value'    => 'hor',
				),
			),
		));
}
add_action('customize_register', 'my_fields');