Provisioning script can't be re-run on already provisioned system

[wkz]

Current Behavior

On a system that has already been provisioned, /mnt/{aux,cfg,var} will be mounted at boot, which means mke2fs will refuse to create filesystems on these partitions:

>>> Creating aux filesystem ...                                 

mke2fs 1.47.0 (5-Feb-2023)

/dev/disk/by-partlabel/aux is mounted; will not make a filesystem here!

!!! Creating aux filesystem                                  ERR

Expected Behavior

The provisioning script should ensure that the partitions involved are unmounted before updating the partition table and creating new filesystems.

Steps To Reproduce

1. Run provisioning script
2. Reboot
3. Run provisioning script

Additional information

No response