Fixes Graves (Citadel-Station-13#5946)

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## About The Pull Request

1. **Fixes Graves.**

## Why It's Good For The Game

1. _Graves were using their old colored sprite and were starting closed
when dug up. This fixes the sprite issue on both fronts._

## Changelog

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:cl:
fix: Fixes Graves.
/:cl:

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code/game/objects/structures/crates_lockers/closets/coffin.dm

@@ -22,7 +22,7 @@
 	desc = "Dirt."
 	icon = 'icons/obj/closets/grave.dmi'
 	closet_appearance = null
-	icon_state = "closed"
+	icon_state = "open"
 	icon_closed = "closed"
 	icon_opened = "open"
 	seal_tool = null