Fixes communications intel objective being instantly completed (#3723)

# About the pull request

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tcomms_startup sets on = TRUE and is called on Initialize(), silly.

This means it just checks when you toggle the state of the tower
(usually to on)

Doesn't check if you inputted the frequencies I guess but eh

# Explain why it's good for the game
Don't give marines free intel they didn't earn

# Testing Photographs and Procedure
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<summary>Screenshots & Videos</summary>

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# Changelog
:cl:
fix: Communications intel objective now actually works
/:cl:

code/game/machinery/telecomms/presets.dm

@@ -60,7 +60,7 @@
 		return TRUE
 	return FALSE
 
-/obj/structure/machinery/telecomms/relay/preset/tower/tcomms_startup()
+/obj/structure/machinery/telecomms/relay/preset/tower/update_state()
 	. = ..()
 	if(on)
 		playsound(src, 'sound/machines/tcomms_on.ogg', vol = 80, vary = FALSE, sound_range = 16, falloff = 0.5)