Communicatino server freewheels when setup node fails

[knoellle]

If a setup node panics or returns an error result, the output provider for that cycler in communication goes into an infinite loop. The issue is here where the result is ignored. wait_for_change returns an Err(NoSender) immediately if the sender has been dropped.

@schmidma does your rewrite handle this correctly?

[schmidma]

No, it currently does not. Good catch. I'll consider that