Makes pizza cheaper. (#3163)

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## About The Pull Request

Makes the cargo pack for pizza cheaper, 6000-3000

## Why It's Good For The Game
a little snack for a reasonable price, still pricier than less tasty
options (donks and rations)

## Changelog

:cl:

balance: Pizzas have become cheaper. (6000 cr - 3000 cr)
/:cl:

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code/modules/cargo/packs/food.dm

@@ -25,7 +25,7 @@
 /datum/supply_pack/food/pizza
 	name = "Pizza Crate"
 	desc = "Best prices on this side of the galaxy. All deliveries are guaranteed to be 99.5% anomaly-free!"
-	cost = 6000 // Best prices this side of the galaxy.
+	cost = 3000// Best prices this side of the galaxy.
 	contains = list(/obj/item/pizzabox/margherita,
 					/obj/item/pizzabox/mushroom,
 					/obj/item/pizzabox/meat,