Install OVS from RDO Train Testing repository for CS8

CentOS Linux 8 repos have been removed from centos mirrors. We were
using that repo to install OVS in multi-node from train repo.

This patch is moving multi-node rolo to install ovs from the RDO testing
repo for train until we have it pushed to the official mirrors for CS8.

Change-Id: Id57e8e90903a0d468c6d3094fbbaf4840a368e2a
1 file changed
tree: 541965def96949740c85ffb6a78fca39eb777074
  1. .gitreview
  3. playbooks/
  4. roles/
  5. zuul.d/