Adds "Merged" and "Closed" stamps (#820)

## About The Pull Request

Adds "Merged" and "Closed" stamps, along with fluff paper containing a
random amount of randomly generated pull requests. They can be found in
a briefcase in the RD's locker, or rarely in maint.


![image](https://github.com/Bubberstation/Bubberstation/assets/8602857/90fc5d89-a7fe-4dfe-8914-10e62abd8b75)

## Why It's Good For The Game

That damn griefer george melons came to me in a dream and asked me to
make funny stamps. They can be found in the research director's locker,
and also in maint.

## Changelog

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🆑 BurgerBB
add: Adds "Merged" and "Closed" stamps. They can be found in the
research director's locker.
/🆑

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code/modules/asset_cache/assets/paper.dm

@@ -18,6 +18,11 @@
 		"stamp-solfed" = 'modular_skyrat/master_files/icons/stamp_icons/large_stamp-solfed.png',
 		// SKYRAT ADDITION: END - Other stamp icons
 
+		//BUBBERSTATION ADDITION: START - Bubberstation Stamp Icons
+		"stamp-merged" = 'icons/stamp_icons/large_stamp-merged.png',
+		"stamp-closed" = 'icons/stamp_icons/large_stamp-closed.png',
+		//BUBBERSTATION ADDITION: END - Bubberstation Stamp Icons
+
 		"stamp-clown" = 'icons/stamp_icons/large_stamp-clown.png',
 		"stamp-deny" = 'icons/stamp_icons/large_stamp-deny.png',
 		"stamp-ok" = 'icons/stamp_icons/large_stamp-ok.png',
@@ -34,4 +39,5 @@
 		"stamp-mime" = 'icons/stamp_icons/large_stamp-mime.png',
 		"stamp-centcom" = 'icons/stamp_icons/large_stamp-centcom.png',
 		"stamp-syndicate" = 'icons/stamp_icons/large_stamp-syndicate.png'
+
 	)