RDO Updates

Promotions
* Latest promotions (TripleO CI):
   * Master CentOS8: 16th April
   * Train: 16th April
   * Stein: 17th April

Packages
* Ansible is being updated to 2.9.7 in Ussuri
* Networking-fujitsu and networking-ovn are removed from Ussuri
* Ovn is updated to 20.03 in Ussuri
* Python-dataclasses (dependency for nova) added to Ussuri
* Ansible-runner is updated to 1.4.5 in Ussuri
* puppet is upgraded to 6.14.0 in CentOS 8

Vexxhost
* ci.centos weirdo jobs are migrated to vexxhost, Other RDO jobs are also being evaluated on

vexxhost
   * https://review.rdoproject.org/r/#/q/topic:vexxhost
* Review.rdoproject.org and softwarefactory-project.io have been successfully migrated from rdo-cloud to vexxhost.

Other
* CentOS8 Updates:-
   * Advanced Virtualization has been built by Virt SIG in CBS and it’s expected that we will be able to start using them soon.
   * CentOS8 Train CBS builds are being pushed to testing repo
      * https://review.rdoproject.org/r/#/c/26277/
   * Some epel packages are added to RDO CentOS8 Ussuri repo, same will be done for CentOS8 train too
      * https://trello.com/c/OmeqSzC8/734-use-mock-from-non-epel-repo
* Rabbitmq is built for CentOS 8 in Messaging SIG. RDO will install it from their repos:
   * https://cbs.centos.org/koji/builds?tagID=2036
* Ussuri Release Preparation:-
   * https://trello.com/c/Fk3CzYKJ/736-ussuri-release-preparation
   * https://review.rdoproject.org/etherpad/p/ussuri-release-preparation
   * https://review.rdoproject.org/r/#/q/topic:ussuri-branching

On behalf or RDO