Bug#922314: python3-x2gobroker: insecure default SSH host key policy

[Linnea Skogtvedt <linnea@linuxavdelingen.no>]

Package: python3-x2gobroker
Version: 0.0.4.0-3

The x2gobroker/agent.py source file contains the following lines in the
_call_remote_broker_agent function:

elif 'host_key_policy' not in remote_agent:
        remote_agent['host_key_policy'] = paramiko.WarningPolicy()

This overrides the paramiko SSH library default which is RejectPolicy. I
believe that should be the default in python3-x2gobroker as well,
because it's the expected default in SSH clients and libraries, and
because the (indirect) caller in broker/base_broker.py does not set a
policy.