[Issue]: Build Centos 7 from CD only

### What went wrong?

Centos 7 can not be built from ISO only. Check if this can be fixed.

### Specify the build host system.

Ubuntu 20.04

### Are you building with docker?

- [X] Yes

### Operating System with Errors

CentOS 7.x

### Which generated disk image is not working?

QCOW2 (KVM, QEMU, Proxmox)

### Relevant log output

_No response_