[MIRROR] Vore test runtime fix (#12151)

Co-authored-by: Will <7099514+Willburd@users.noreply.github.com>

code/modules/unit_tests/vore_tests.dm

@@ -1,6 +1,8 @@
 /datum/unit_test/proc/create_test_human(turf/loc = null)
 	if(!loc)
 		for(var/turf/simulated/floor/tiled/T in world)
+			if(!T.zone)
+				continue
 			var/pressure = T.zone.air.return_pressure()
 			if(90 < pressure && pressure < 120) // Find a turf between 90 and 120
 				loc = T