Description of problem:

Registering a bootc image mode host reports failure:

#
# Running registration
#
Unregistering from: a-computer.example.com:443/rhsm
System has been unregistered.
All local data removed
subscription-manager is already installed!
The system has been registered with ID: df250fbd-8bd4-481e-80fc-c3b8f5a78a48
The registered system name is: localhost.localdomain
# Running [localhost.localdomain] host initial configuration
chown: changing ownership of '/root': Read-only file system
Host [localhost.localdomain] initial configuration failed
Successfully updated the system facts. 

The chown part comes from the remote execution ssh key template.

If you disable setting up REX during registration, the registration succeeds.

How reproducible:

100%

Is this issue a regression from an earlier version:

No

Steps to Reproduce:

Register a bootc host to Foreman with REX being set up.

Actual behavior:

Error happens

chown: changing ownership of '/root': Read-only file system Host [localhost.localdomain] initial configuration failed

Expected behavior:

No error happens

Business Impact / Additional info:

The code that causes this is here: https://github.com/theforeman/foreman/blob/3.13-stable/app/views/unattended/provisioning_templates/snippet/remote_execution_ssh_keys.erb#L60

[root@localhost ~]# chown -R root: ~root
chown: changing ownership of '/root': Read-only file system

DEV Tracker for https://issues.redhat.com/browse/SAT-29454