Repopulate BBS if empty

There is an infrequent issue where the BBS will show up empty on a
game reload as SpaceStation.adverts[station] is missing.
This fix will cause the BBS to repopulate itself but only from
those modules that impements onUpdateBB(). It will not solve the
underlying cause.

Addresses #5886

data/libs/SpaceStation.lua

@@ -901,9 +901,8 @@ end
 local function updateAdverts (station)
 	if not SpaceStation.adverts[station] then
 		logWarning("SpaceStation.lua: updateAdverts called for station that hasn't been visited")
-	else
-		Event.Queue("onUpdateBB", station)
 	end
+	Event.Queue("onUpdateBB", station)
 end
 
 --