Remove redundant cleanup of /atom/var/reagents

* /datum/reagents/Destroy() does everything /datum/reagents/delete() does and more, and delete() is called only from /obj/effect/Destroy() which is *itself* redundant with its parent /atom/movable/Destroy()

code/game/objects/effects/effect_system.dm

@@ -13,11 +13,6 @@ would spawn and follow the beaker, even if it is carried or thrown.
 	unacidable = 1//So effect are not targeted by alien acid.
 	pass_flags = PASSTABLE | PASSGRILLE
 
-/obj/effect/Destroy()
-	if(reagents)
-		reagents.delete()
-	return ..()
-
 /datum/effect/effect/system
 	var/number = 3
 	var/cardinals = 0