How to Hide Auto-Install Free SSL Admin Menus

function plt_hide_auto_install_free_ssl_menus() {
	//Hide "Auto-Install Free SSL".
	remove_menu_page('auto_install_free_ssl');
	//Hide "Auto-Install Free SSL → Auto-Install Free SSL".
	remove_submenu_page('auto_install_free_ssl', 'auto_install_free_ssl');
	//Hide "Auto-Install Free SSL → Generate SSL".
	remove_submenu_page('auto_install_free_ssl', 'aifs_generate_ssl_manually');
	//Hide "Auto-Install Free SSL → Force HTTPS".
	remove_submenu_page('auto_install_free_ssl', 'aifs_force_https');
	//Hide "Auto-Install Free SSL → Log".
	remove_submenu_page('auto_install_free_ssl', 'aifs_log');
	//Hide "Auto-Install Free SSL → Free vs. Premium".
	remove_submenu_page('auto_install_free_ssl', 'auto_install_free_ssl-free-vs-premium');
	//Hide "Auto-Install Free SSL → Affiliation".
	remove_submenu_page('auto_install_free_ssl', 'auto_install_free_ssl-affiliation');
	//Hide "Auto-Install Free SSL → Support Forum".
	remove_submenu_page('auto_install_free_ssl', 'auto_install_free_ssl-wp-support-forum');
	//Hide "Auto-Install Free SSL → Upgrade".
	remove_submenu_page('auto_install_free_ssl', 'auto_install_free_ssl-pricing');
}

add_action('admin_menu', 'plt_hide_auto_install_free_ssl_menus', 1000000000);

Where do I put this code?