fix for issues if zero or 1 interfaces in vrf
fix for issues if zero or 1 interfaces in vrf

ckishimo/napalm-junos,spotify/napalm,pshemk/napalm-junos,mirceaulinic/napalm-junos,napalm-automation/napalm,spotify/napalm,napalm-automation/napalm-junos