ACME logger path repeatedly duplicates "maintenance" segments #854

Logger path accumulates repeated "maintenance" segments (tls.loader.acme/maintenance/maintenance/...), producing noisy lines when ACME renewals run.

Repro (assume defaults):

Enable ACME in maddy.
Wait for renewal/maintenance cycle.
Observe tls.loader.acme log entries.

Observed:
tls.loader.acme/maintenance/maintenance/...: got renewal info { ... }
tls.loader.acme/maintenance/maintenance/...: updated and stored ACME renewal information { ... }

Expected:
tls.loader.acme/maintenance: got renewal info { ... }
tls.loader.acme/maintenance: updated and stored ACME renewal information { ... }

Sanitized example:
tls.loader.acme/maintenance/maintenance/...: got renewal info {"cert_expiry":"","identifiers":[""],"next_ari_update":"","remote_ip":""}
tls.loader.acme/maintenance/maintenance/...: updated and stored ACME renewal information {"cert_expiry":"","next_update":"","remote_ip":""}

maintenance line grows every update cycle