How to Hide the "IT-Recht Kanzlei" Admin Menu

function plt_hide_legal_texts_connector_it_recht_kanzlei_menus() {
	//Hide the "Settings → IT-Recht Kanzlei" menu.
	remove_submenu_page('options-general.php', 'legal_texts_connector_settings');
}

add_action('admin_menu', 'plt_hide_legal_texts_connector_it_recht_kanzlei_menus', 11);

Where do I put this code?