fixes a runtime in portable_turret (#4259)

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## About The Pull Request
Fixes #4256 
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## Why It's Good For The Game
runtime bad
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## Changelog

:cl:
fix: fixes a flaky test runtime from a a string not being wrapped in a
list in portable_turret.dm
/:cl:

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code/game/machinery/porta_turret/portable_turret.dm

@@ -513,7 +513,7 @@
 
 		//this is still a bit gross, but less gross than before
 		var/static/list/dangerous_fauna = typecacheof(list(/mob/living/simple_animal/hostile, /mob/living/carbon/alien, /mob/living/carbon/monkey))
-		if(!is_type_in_typecache(target_mob, dangerous_fauna) || faction_check("neutral", target_mob.faction))
+		if(!is_type_in_typecache(target_mob, dangerous_fauna) || faction_check(list("neutral"), target_mob.faction))
 			return FALSE
 
 		if(istype(target_mob, /mob/living/simple_animal/hostile/retaliate))