apt.systemd.daily job logs about incorrect switch being used

[Ernst Kloppenburg]

The script /usr/lib/apt/apt.systemd.daily produces log entries in the systemd journal like
   unattended-upgrade -d (success)
or
   unattended-upgrade -d (error)

These seem to imply that "unattended-upgrade" was run with the command line flag "-d", which according to the manpage means "debug".

But actually "unattended-upgrade" was run with the option "--download-only".

I would be easier to understand and debug the u-a behavior if the log entries would reflect this clearly.

(Ubuntu 16.04.3 LTS, apt 1.2.24)

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: apt 1.2.24
ProcVersionSignature: Ubuntu 4.10.0-33.37~16.04.1-generic 4.10.17
Uname: Linux 4.10.0-33-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.10
Architecture: amd64
CurrentDesktop: KDE
Date: Sat Sep 23 10:18:06 2017
InstallationDate: Installed on 2014-08-28 (1121 days ago)
InstallationMedia: Kubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140416.1)
SourcePackage: apt
UpgradeStatus: Upgraded to xenial on 2016-05-20 (490 days ago)