Secret documents black market item properly randomizes its documents (#…

…3041)

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## About The Pull Request

Wrong subtype 

## Why It's Good For The Game

There is only one person who would notice this and its. Me

## Changelog

:cl:
fix: black market secret documents are no longer default documents
/:cl:

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code/modules/cargo/blackmarket/blackmarket_items/misc.dm

@@ -91,7 +91,7 @@
 	stock = 1
 	availability_prob = 40
 
-/datum/blackmarket_item/consumable/secret_docs/spawn_item(loc)
+/datum/blackmarket_item/misc/secret_docs/spawn_item(loc)
 	var/docs = pick(list(/obj/item/documents/nanotrasen,
 				/obj/item/documents/solgov,
 				/obj/item/documents/terragov,