CargoDestination::station can be nil on read when type is station

[Quezler]

on the space exploration discord we had to do an emergency hotfix for it: https://discord.com/channels/4195267147 ... 4193514567

basically the docs make you believe they're marked as optional since they only appear when the type matches theirs, but apparently when the type is station the station itself could return as nil, it is hard to tell wether this was a rare occurence or not, and wether this is a documentation issue or a game bug.

in either case it would be nice if it could mention it might still be nil despite the cargo destination's type being station.