Parity for small ships (#3436)

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## About The Pull Request

Nixes the extra deckhand from Kilo and increases the Mudskipper's spawn
limit by 1. Hopefully we don't just get those maxed out every single
round.

## Why It's Good For The Game

Brings the two smallest ships in the game into parity with each other,
and provides at least a little more flexibility for players that respawn
or come in late.

## Changelog

:cl:
balance: increased mudskipper limit to 2
balance: cut a deckhand slot from kilo
/:cl:

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_maps/configs/independent_kilo.json

@@ -31,7 +31,7 @@
 		},
 		"Deckhand": {
 			"outfit": "/datum/outfit/job/independent/assistant",
-			"slots": 2
+			"slots": 1
 		}
 	},
 	"enabled": true

_maps/configs/independent_mudskipper.json

@@ -15,7 +15,7 @@
 		"SPACE"
 	],
 	"map_path": "_maps/shuttles/independent/independent_mudskipper.dmm",
-	"limit": 1,
+	"limit": 2,
 	"starting_funds": 1500,
 	"job_slots": {
 		"Salvage Leader": {