How to Hide the "CSP settings" Admin Menu

function plt_hide_no_unsafe_inline_menus() {
	//Hide the "Settings → CSP settings" menu.
	remove_submenu_page('options-general.php', 'no-unsafe-inline');
}

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

Where do I put this code?