Fixing one slight issue.

I'm an idiot, forgot about garbage collecting. This fixes a slight issue
in my previous PR that would have eventually resulted in a call of DEL
if nobody rebuilt the console.

code/modules/xenobio2/machinery/injector_computer.dm

@@ -20,6 +20,7 @@
 	var/active
 
 /obj/machinery/computer/xenobio2/Destroy()
+	injector.computer = null
 	..()
 
 /obj/machinery/computer/xenobio2/attack_hand(mob/user)