Disaster recovery procedure enhancements

[DavidePrincipi]

Improve restoration of Traefik within the disaster recovery procedure.

Proposed solution

Modify the cluster/restore-module action to handle Traefik's restore differently. Instead of creating a new module instance as usual, run the module's restore-module action, which, in turn, must merge the backup contents with the existing module's configuration.

Alternative solutions

Refer to #7164. In summary, this involves adding a no_data_backup flag to Traefik and completely disabling backups for the Traefik module.

See also

• Discussion: https://mattermost.nethesis.it/nethesis/pl/erf8zdetktd9tm853nkh4dwptc
• GitHub Project: NethServer (view)
• Community Forum: https://community.nethserver.org/t/nethserver-project-milestone-8-2/24747#p-170826-compass-roadmap-14