[Maps] Fix incorrect fruit bush in Gulf of Bothnia - Frozen Lake biome

"fruitBush": "gaia/fauna_deer" was an oversight/ hack and is just bad
practice.

patch by: @real_tabasco_sauce
comments by: @phosit
Differential revision: https://code.wildfiregames.com/D4990
This was SVN commit r27635.

binaries/data/mods/public/maps/random/rmbiome/gulf_of_bothnia/frozen_lake.json

@@ -50,7 +50,7 @@
 		"tree3": "gaia/tree/temperate_winter",
 		"tree4": "gaia/tree/fir_winter",
 		"tree5": "gaia/tree/temperate_winter",
-		"fruitBush": "gaia/fauna_deer",
+		"fruitBush": "gaia/fruit/berry_02",
 		"chicken": "gaia/fauna_chicken",
 		"mainHuntableAnimal": "gaia/fauna_deer",
 		"secondaryHuntableAnimal": "gaia/fauna_deer",