[MIRROR] Adds 2 new maintenance ambience tracks. [MDB IGNORE] (#23474)

* Adds 2 new maintenance ambience tracks. (#78053)

## About The Pull Request

Check em
ambimaint6.ogg
https://voca.ro/18Z7uzi10WEu
ambimaint7.ogg
https://voca.ro/1kRJ2akcYxdy

both around the same length as the other ambimaint tracks

theres no attributions bcuz all samples used are of my own creation

## Why It's Good For The Game

I have heard that maintenance ambience as it stands is considered
repetitive and in need of more clanky clonky sounds

## Changelog

🆑
sound: 2 new ambient tracks for maintenance tunnels
/🆑

* Adds 2 new maintenance ambience tracks.

---------

Co-authored-by: Capsandi <38051413+Capsandi@users.noreply.github.com>

code/_globalvars/lists/ambience.dm

@@ -128,6 +128,8 @@ GLOBAL_LIST_INIT(maint_ambience,list(
 	'sound/ambience/ambimaint3.ogg',
 	'sound/ambience/ambimaint4.ogg',
 	'sound/ambience/ambimaint5.ogg',
+	'sound/ambience/ambimaint6.ogg',
+	'sound/ambience/ambimaint7.ogg',
 	'sound/ambience/ambitech2.ogg',
 	'sound/voice/lowHiss1.ogg',
 	'sound/voice/lowHiss2.ogg',

sound/ambience/license.txt

@@ -11,4 +11,7 @@ title3.ogg is Tintin On The Moon remixed by Cuboos https://tgstation13.org/phpBB
 
 VoidsEmbrace.ogg is Chopin - Waltz in C Sharp Minor (Op. 64 No. 2). It is in public domain.
 
+ambispace4.ogg is Sipping Bird, by Capsandi. It has been licensed under CC-BY 3.0 license.
+ambimaint6.ogg and ambimaint7.ogg, created by Capsandi are licensed under CC-BY 3.0 license.
+
 CC-BY 3.0: http://creativecommons.org/licenses/by/3.0/