N2O no longer puts you into a coma (#2850)

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## About The Pull Request

Replaces add sleep with set sleep for nitrous so the current sleep +4
seconds doesnt stack with itself to comically high numbers

## Why It's Good For The Game

If i wanted to sleep id get a blanket not a silly tank

## Changelog

:cl:
fix: anesthetic can no longer semi permanently knock people out
/:cl:

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Signed-off-by: Theos <[email protected]>

code/modules/surgery/organs/lungs.dm

@@ -226,7 +226,7 @@
 		if(SA_pp > SA_para_min) // Enough to make us stunned for a bit
 			H.Unconscious(60) // 60 gives them one second to wake up and run away a bit!
 			if(SA_pp > SA_sleep_min) // Enough to make us sleep as well
-				H.Sleeping(max(H.AmountSleeping() + 40, 200))
+				H.Sleeping(200)
 		else if(SA_pp > 0.01)	// There is sleeping gas in their lungs, but only a little, so give them a bit of a warning
 			if(prob(20))
 				H.emote(pick("giggle", "laugh"))