How to Hide the "Eliminate Render Blocking CSS" Admin Menu

function plt_hide_eliminate_render_blocking_css_menus() {
	//Hide the "Settings → Eliminate Render Blocking CSS" menu.
	remove_submenu_page('options-general.php', 'eliminate_render_blocking_css');
}

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

Where do I put this code?