Use mock SystemManager in test_discovery
Use mock SystemManager in test_discovery

Change-Id: Ib81598daf611355f619dbc89fcfb611c14c167fa
Related-Bug: 1531023

tcpcloud/contrail-controller,eonpatapon/contrail-controller,eonpatapon/contrail-controller,nischalsheth/contrail-controller,sajuptpm/contrail-controller,nischalsheth/contrail-controller,nischalsheth/contrail-controller,eonpatapon/contrail-controller,tcpcloud/contrail-controller,rombie/contrail-controller,rombie/contrail-controller,sajuptpm/contrail-controller,eonpatapon/contrail-controller,codilime/contrail-controller,eonpatapon/contrail-controller,nischalsheth/contrail-controller,rombie/contrail-controller,tcpcloud/contrail-controller,tcpcloud/contrail-controller,codilime/contrail-controller,sajuptpm/contrail-controller,rombie/contrail-controller,tcpcloud/contrail-controller,rombie/contrail-controller,eonpatapon/contrail-controller,rombie/contrail-controller,sajuptpm/contrail-controller,nischalsheth/contrail-controller,codilime/contrail-controller,eonpatapon/contrail-controller,nischalsheth/contrail-controller,rombie/contrail-controller,nischalsheth/contrail-controller,codilime/contrail-controller,sajuptpm/contrail-controller,codilime/contrail-controller,nischalsheth/contrail-controller,tcpcloud/contrail-controller,sajuptpm/contrail-controller,codilime/contrail-controller