- install ipref3 using virt-customize
- enables QoS server test on DevStack based setups
- remove iperf3 installation from iperf3 shell APIs
- raise default QoS BW limit from 1Kbps to 1 Mbps
- increase QoS bandwith limit tollerance range (90%-110%)
Depends-On: https://review.opendev.org/c/x/devstack-plugin-tobiko/+/788899
Change-Id: Idc7d98b34ce59d14408b15edb6061a36f796a8fc