Makes Plastic Flaps no longer airtight (#2969)

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## About The Pull Request
# You cannot tell me these fucking things are blocking the vacuum of
space.

![Baggage-Claim-Strip-Curtain-Kit-Shop-All-StripCurtaincom_500__00450](https://github.com/shiptest-ss13/Shiptest/assets/95449138/e9397556-db2f-4fac-aa05-5c4fa490ec93)
(Makes plastic flaps no longer block atmos and changes the name and desc
to match.)
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## Why It's Good For The Game
Players should not be able to construct a budget-tinyfan for 5 plastic
with only the caveat of having to crawl under it. Using these to cover
bay doors has been frowned upon for a while and it should have been
fixed when tinyfans were phased out.
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## Changelog

:cl:
del: Plastic flaps no longer block atmos
/:cl:

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code/game/objects/structures/plasticflaps.dm

@@ -1,13 +1,12 @@
 /obj/structure/plasticflaps
-	name = "airtight plastic flaps"
-	desc = "Heavy duty, airtight, plastic flaps. Definitely can't get past those. No way."
+	name = "plastic flaps"
+	desc = "Heavy duty plastic flaps. Definitely can't get past those. No way."
 	gender = PLURAL
 	icon = 'icons/obj/stationobjs.dmi'
 	icon_state = "plasticflaps"
 	armor = list("melee" = 100, "bullet" = 80, "laser" = 80, "energy" = 100, "bomb" = 50, "bio" = 100, "rad" = 100, "fire" = 50, "acid" = 50)
 	density = FALSE
 	anchored = TRUE
-	CanAtmosPass = ATMOS_PASS_NO
 
 /obj/structure/plasticflaps/opaque
 	opacity = TRUE