Suit storages qdel pockets on Destroy() (#6990)

# About the pull request

When `Destroy()`ing, suit storages will now qdel and clean their
reference to the `pockets` var.

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# Explain why it's good for the game

Harddels bad.
# Testing Photographs and Procedure
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# Changelog
No player facing changes.

code/modules/clothing/suits/storage.dm

@@ -10,6 +10,10 @@
 	pockets.max_storage_space = 4
 	flags_atom |= USES_HEARING
 
+/obj/item/clothing/suit/storage/Destroy()
+	QDEL_NULL(pockets)
+	return ..()
+
 /obj/item/clothing/suit/storage/get_pockets()
 	if(pockets)
 		return pockets