Draft: Automate Redis deployment for critical sites

TODO

• automate Redis deployment for QoS "critical" sites
• automate enabling the Redis drupal module (with drush)
• pass Redis password to server pod env var REDIS_PASSWORD

Redis can be deployed as a separate deployment in the namespace. We have successfully deployed it with the OKD4 template from upstream. I also deployed it with the bitnami Helm chart, but openshift sounds simpler (?). See more in https://gitlab.cern.ch/webservices/webframeworks-planning/-/issues/200

partial https://gitlab.cern.ch/webservices/webframeworks-planning/-/issues/200