Fixes lattice duplicate check (#21740)

code/game/objects/structures/lattice.dm

@@ -59,7 +59,7 @@
 
 /obj/structure/lattice/proc/check_for_duplicates()
 	for(var/obj/structure/lattice/found_lattice in get_turf(src))
-		if(found_lattice == src || istype(found_lattice, /obj/structure/lattice/ceiling))
+		if(found_lattice == src || found_lattice.type != src.type) // if the instance we're comparing is us or a different type, then it's not a duplicate
 			continue
 		return TRUE
 	return FALSE
@@ -99,13 +99,6 @@
 	. = ..()
 	AddComponent(/datum/component/large_transparency, 0, 0, 0, 0)
 
-/obj/structure/lattice/ceiling/check_for_duplicates()
-	for(var/obj/structure/lattice/ceiling/found_lattice in get_turf(src))
-		if(found_lattice == src)
-			continue
-		return TRUE
-	return FALSE
-
 /obj/structure/lattice/catwalk
 	name = "catwalk"
 	desc = "A catwalk for easier EVA maneuvering."