UEFI not booting from mounted CD

[benjamin-crill]

Trying to update a Packer build from legacy BIOS to UEFI for Packer. Previous build works fine, however when making it UEFI then it never boots from the mounted ISO and then tries to network boot. Trying to add the boot_priority and specify cdrom comes back with a validation error on the Packer side. I can't seem to find any Packer examples with UEFI and the documentation seems to allude there isn't a way to do this unless using ACLI or the UEFI boot manager from the console which takes away some of the value of automation.