no more ice demon capture missions (#3421)

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## About The Pull Request

Have fun capturing the thing that teleports every 3 seconds and quickly
runs away from you

## Why It's Good For The Game

You can probably accomplish these but it's terribly tedious and horribly
not worth it

## Changelog

:cl:
del: missions will no longer request capturing ice demons
/:cl:

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code/modules/overmap/missions/acquire_mission.dm

@@ -180,14 +180,6 @@ Acquire: Anomaly
 	weight = 2
 	objective_type = /mob/living/simple_animal/hostile/asteroid/ice_whelp
 
-/datum/mission/acquire/creature/ice_demon
-	name = "Capture an ice demon"
-	desc = "I require a live ice demon for research purposes. Trap one within the given \
-			Lifeform Containment Unit and return it to me and you will be paid handsomely."
-	value = 1500
-	weight = 2
-	objective_type = /mob/living/simple_animal/hostile/asteroid/ice_demon
-
 /datum/mission/acquire/creature/migo
 	name = "Capture a live mi-go"
 	desc = "I require a live mi-go for research purposes. Trap one within the given \