Added a pipeline file (tests/azure/build-containers.yml) to build test
containers and upload them to quay.io. The pipeline will create
containers with IPA pre-installed for testing proposes on three
different Linux containers: CentOS 7, CentOS 8 and Fedora Latest.
Added comment about problem with no_log in Azure CI. While running on CI
using ansible 2.10a the content of attributes with no_log=True is
replaced by ***** on ansible causing test failures.
* Moved azure CI definitions from azure-pipelines.yml to
tests/azure/azure-pipelines.yml.
* Updated azure CI definitions to run playbook tests using docker
containers.