
Expose additional Horizon security params in accordance with the OpenStack Security Guide [0] - ALLOWED_HOSTS - HORIZON_IMAGES_UPLOAD_MODE [0] https://docs.openstack.org/security-guide/dashboard/domains-dashboard-upgrades-basic-web-server-configuration.html Depends-On: https://review.opendev.org/#/c/635545 Change-Id: I071c8fbfc5ea9b41d3c35840e342d83349ae1613