auditd creates an ordering cycle by adding wantedBy = [ "basic.target" ],
because of this the job job systemd-update-utmp.service/start is deleted.
Adding unitConfig.DefaultDependencies = false; to the auditd service unbreaks the cycle.
See also #11864
#11864 Support Linux audit subsystem
Add the auditd.service as NixOS module to be able to
generate profiles from /var/log/audit/audit.log
with apparmor-utils.
auditd needs the folder /var/log/audit to be present on start
so this is generated in ExecPreStart.
auditd starts with -s nochange so that effective audit processing
is managed by the audit.service.