Nyx doesn't tolerate lack of debian-tor account

[MikeBishop]

I'm running a Tor bridge in a container (using https://hub.docker.com/r/thetorproject/obfs4-bridge), and using nyx on the host to monitor it. Nyx is persistently logging this error message:

[NYX_NOTICE] BUG: Unexpected exception from ConnectionTracker: "getpwnam(): name not found:
'debian-tor'" [122 duplicates hidden]

Presumably this is because the debian-tor user only exists inside the container. Nyx needs to be more tolerant of the possibility that its environment is not the same as the tor process it's monitoring.