[D3XP] Exit Elevator's GUI does not update clientside at Erebus Sector 2

[Stradex]

The Exit Elevator's GUI does not update clientside after the last power cell is placed in order to be able to leave the map, and because the Exit Elevator's GUI does not update then clients still see the message that says "Power failure" or something like that at the exit gui's, although they can still press it and exit the map. This is mostly a visual desync bug, not vital but annoying for sure.