Removes /obj/onShuttleMove invisibility check

The two invisible objects that shouldn't move now have their own
dedicated overrides

code/modules/shuttle/on_move.dm

@@ -8,19 +8,12 @@
 /atom/movable/lighting_overlay/onShuttleMove()
     return 0
 
-/obj/onShuttleMove()
-    if(invisibility >= 101)
-        return 0
-    . = ..()
-
-/obj/effect/landmark/onShuttleMove()
-    // Drop invisibility juuust enough to get moved
-    invisibility = 100
-    . = ..()
-    invisibility = 101
-
 /obj/effect/landmark/shuttle_import/onShuttleMove()
-    // Unless you're THIS landmark
+    // Used for marking where to preview/load shuttles
+    return 0
+
+/obj/docking_port/onShuttleMove()
+    // Stationary ports shouldn't move, mobile ones move themselves
     return 0
 
 /obj/machinery/door/onShuttleMove()