Add support for building AlmaLinux and RockyLinux images, and associated image_ci test pipeline
- A8 and R8 images will not be published, this commit exists solely to build and test the images
- a new kickstart exists for A8/R8
elc8-cloud.ks. This has been done to configure the CERN repo manually, and ensure thatcentospackages are not installed.
Edited by Ben Morrice