mod_pubsub_summary: Use pre-escaped UTF-8 sequence for compat This silences a warning about using the non-existent global 'utf8' each time this line was hit. The utf8 library was introduced in Lua 5.3, so the warning would appear with 5.1 and 5.2.

module:set_global();

local log = _G.log;

module:add_timer(60-os.date("%S"), function (now)
	log("info", "-- MARK --");
	return 90 - ((now + 30) % 60);
end);