Gives the Riggs a touch-up (#2721)

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## About The Pull Request

![rigger_remap](https://github.com/shiptest-ss13/Shiptest/assets/60533805/53fce13e-7ed8-46de-a878-077bf0614077)
The Riggs has aged incredibly well for being one of the oldest maps
still in rotation, but it's definitely fallen out of line with newer
ships as standards have been updated. This PR brings it in line with
those standards and freshens up the layout and decoration a bit.

- Removed RnD and ORM
- Added separate cryo room
- Added crew lounge area and miner ready room
- Moved atmos slightly to make accessing the empty rooms easier and
replaced the standing air tanks with a 1-tile open air tank (temporary,
really, until we get better tanks coded)
- Added access restrictions to atmos and engine room (but not
engineering bay)
- Reduced miner slots to 1 and assistant slots to 2
- Removed Mech Technician

## Why It's Good For The Game

Riggs was getting crusty and needed some love.
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## Changelog

:cl:
tweak: Made the Riggs-class sloop nicer to live in
balance: Removed RnD and ORM from the Riggs
/:cl:

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_maps/configs/independent_rigger.json

@@ -1,19 +1,17 @@
 {
 	"$schema": "https://raw.githubusercontent.com/shiptest-ss13/Shiptest/master/_maps/ship_config_schema.json",
 	"map_name": "Riggs-class Sloop",
-	"prefix": "ISV",
+	"prefix": "SV",
 	"namelists": [
 		"GENERAL",
 		"SPACE",
-		"NATURAL",
-		"NATURAL_AGGRESSIVE"
+		"NATURAL"
 	],
 	"map_short_name": "Riggs-class",
-	"description": "The Rigger-class is Kasagi-Fischer Partnership’s mainstay in the independent ship market. Spacious, affordable, and versatile, Riggers offer basic capabilities for everything a Frontier spacer might need in a convenient, easy-to-modify platform, and by default come equipped with a basic medbay, a small security office, atmospherics recycling and equipment to support an APLU utility mech. Thanks to this versatility, Riggers have become extremely popular among moderately-wealthy independent captains, and can be found doing everything from mining to shipping to surveying Frontier planets.",
+	"description": "The Riggs-class is Kasagi-Fischer Partnership’s mainstay in the independent ship market. Spacious, affordable, and versatile, the Riggs offers basic capabilities for everything a Frontier spacer might need in a convenient, easy-to-modify platform, and by default come equipped with a basic medbay, a small security office, atmospherics recycling and equipment to support an APLU utility mech. Thanks to this versatility, the Riggs has become extremely popular among moderately-wealthy independent captains, and can be found doing everything from mining to shipping to surveying Frontier planets.",
 	"tags": [
 		"Mining",
 		"Medical",
-		"Robotics",
 		"Generalist"
 	],
 	"map_path": "_maps/shuttles/independent/independent_rigger.dmm",
@@ -36,14 +34,10 @@
 		},
 		"Machinist's Mate": {
 			"outfit": "/datum/outfit/job/independent/engineer",
-			"slots": 2
+			"slots": 1
 		},
 		"Asteroid Miner": {
 			"outfit": "/datum/outfit/job/independent/miner",
-			"slots": 2
-		},
-		"Mech Technician": {
-			"outfit": "/datum/outfit/job/independent/roboticist",
 			"slots": 1
 		},
 		"Security Detail": {
@@ -52,7 +46,7 @@
 		},
 		"Deckhand": {
 			"outfit": "/datum/outfit/job/independent/assistant",
-			"slots": 4
+			"slots": 2
 		}
 	},
 	"enabled": true