Makes double bedsheets craftable. (shiptest-ss13#3003)

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## About The Pull Request

Double beds have been craftable for a while, HOWEVER double bedsheets
have been largely rare. That ends NOW.

## Why It's Good For The Game

lets blorbos be comfy

## Changelog

:cl:
add: Double bedsheets, fit for double beds, are now craftable via cloth.
/:cl:

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code/game/objects/items/stacks/sheets/sheet_types.dm

@@ -249,6 +249,7 @@ GLOBAL_LIST_INIT(cloth_recipes, list ( \
 	new/datum/stack_recipe("rag", /obj/item/reagent_containers/glass/rag, 1), \
 	new/datum/stack_recipe("towel", /obj/item/towel, 2), \
 	new/datum/stack_recipe("bedsheet", /obj/item/bedsheet, 3), \
+	new/datum/stack_recipe("double bedsheet", /obj/item/bedsheet/double, 4), \
 	new/datum/stack_recipe("empty sandbag", /obj/item/emptysandbag, 4), \
 	null, \
 	new/datum/stack_recipe("fingerless gloves", /obj/item/clothing/gloves/fingerless, 1), \