Mapping helper fixes (shiptest-ss13#3850)

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## About The Pull Request

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Fixes mapping helpers for seals and notes. They attached their payloads
to the helper instead of the airlock, sending them to the shadow realm.

## Why It's Good For The Game

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Fixes good

## Changelog

:cl:
fix: Sealed and note placer mapping helper
/:cl:

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code/modules/mapping/mapping_helpers.dm

@@ -161,7 +161,7 @@
 	if(airlock.seal)
 		log_mapping("[src] at [AREACOORD(src)] tried to seal [airlock] but it's already already got a seal? What the hell!")
 	else
-		airlock.seal = new /obj/item/door_seal(src)
+		airlock.seal = new /obj/item/door_seal(airlock)
 
 
 
@@ -383,7 +383,7 @@ INITIALIZE_IMMEDIATE(/obj/effect/mapping_helpers/no_lava)
 			found_airlock.update_appearance()
 			qdel(src)
 		if(note_info)
-			var/obj/item/paper/paper = new /obj/item/paper(src)
+			var/obj/item/paper/paper = new /obj/item/paper(found_airlock)
 			if(note_name)
 				paper.name = note_name
 			paper.add_raw_text("[note_info]")