Warning logged on server shutdown

[dlqqq]

[3coins]

@dlqqq
I wasn't able to replicate this in regular flow of launching jlab, creating a chat and shutting down. I saw this error only when I deleted a chat, and shutdown jlab, which seems to be an issue I have observed without the router installed as well. The exception thrown in that log seems harmless, as the rest of the code chain seems to have completed. Let me know if I missed anything.

[dlqqq]

I agree. I think the server being unable to shutdown is just a side-effect of Jupyter Collaboration. Renamed this issue to be more accurate.