Image for CycleCloud VM is not set by the linux_base_image parameter in the config

[egmsft]

With terraform, setting the linux_base_image parameter in the config results in all infra VMs getting deployed with the image referenced by that parameter, with the exception of the CycleCloud VM. The CycleCloud has another parameter that allows specification of the image. The CycleCloud VM uses the CentOS image by default.

1. The default should probably be updated to AlmaLinux
2. Should azhop also use the linux_base_image parameter to select the image version for the CycleCloud VM or should the azhop documentation be updated to point out how the image should be configured for CycleCloud?