Force UTC±0 for time2text logging and IC times (#90347)

## About The Pull Request
This won't actually do anything on live, since those are all set to
UTC±0 currently

Pins logging and IC uses of time2text to UTC±0 instead of using the
system timezone (byond default)
Timezones not being set to utc0 caused issues before (and is again)

All timezones are now passed explicitly to make it more likely it's
cargo culted properly at least

Deletes worldtime2text cus it was gameTimestamp default args

## Why It's Good For The Game
Server timezone changes probably shouldn't affect logging, round times,
file hashes, IC time, when you caught fish, etc

## Changelog
🆑
refactor: Logging and IC timestamps will now always use UTC±0 and not be
affected by server system timezone changes
fix: Station and round times will not longer be incorrect if the system
timezone is not UTC±0
/🆑

---------

Co-authored-by: TiviPlus <572233640+TiviPlus@users.noreply.com>

code/modules/modular_computers/file_system/programs/signalcommander.dm

@@ -79,7 +79,7 @@
 	if(user)
 		computer.balloon_alert(user, "signaled")
 
-	var/time = time2text(world.realtime,"hh:mm:ss")
+	var/time = time2text(world.realtime,"hh:mm:ss", TIMEZONE_UTC)
 	var/turf/T = get_turf(computer)
 	var/user_deets
 	if(signaling)