The publisher's `enable` default read `deploy.authelia.enable` from the
publisher's own module (swarm-secret-publisher.nix). It now defaults to
`false`, and glue-secret-publisher-authelia.nix sets it `mkDefault true`
wherever authelia runs, so the effective value is unchanged. The option
loses its `defaultText`, and its description names the glue.
The `deploy.authelia.enable` read in `active` stays: every file the unit
copies is under authelia's `hostClientSecretDir`, so it is a requirement
of the unit, not a co-location toggle.
Part of #3742.
