How to Hide the "Rich Context" Admin Menu

function plt_hide_rich_context_experience_embed_menus() {
	//Hide the "Settings → Rich Context" menu.
	remove_submenu_page('options-general.php', 'richcontext-embed');
}

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

Where do I put this code?