Restores CentCom (Demeter) Landmark (#5945)

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## About The Pull Request

1. **Puts the Overmap Landmark Back on Map.**

## Why It's Good For The Game

1. _I'm not sure how it got removed, but I tried to fly the Quicksilver
over to the station the other day and it was completely broken. This
fixes the overmap presence for the Demeter._

## Changelog

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:cl:
fix: Restores Demeter OM Landmark.
/:cl:

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maps/rift/levels/rift-11-orbital.dmm

@@ -1273,7 +1273,6 @@
 "ek" = (
 /obj/machinery/door/window/holowindoor{
 	base_state = "right";
-	dir = 2;
 	icon_state = "right";
 	name = "Red Corner"
 	},
@@ -8858,6 +8857,10 @@
 /obj/structure/bed/chair/backed_grey,
 /turf/simulated/floor/reinforced,
 /area/centcom/command)
+"Pc" = (
+/obj/overmap/entity/visitable/sector/centcom,
+/turf/space,
+/area/space)
 "Pf" = (
 /obj/effect/floor_decal/spline/plain,
 /turf/simulated/floor/tiled/techfloor/grid,
@@ -10254,7 +10257,7 @@ hP
 hP
 hP
 hP
-hP
+Pc
 hP
 hP
 hP