Bug#1109842: apt-daily-upgrade.service creates /etc/apt/sources.list

This issue is caused by unattended-upgrade, and is 100% reproducible. 
Reassigning as such.

root@mail:~# /usr/bin/unattended-upgrade -v
Checking if system is running on battery is skipped. Please install 
powermgmt-base package to check power status and skip installing updates when 
the system is running on battery.
Checking if connection is metered is skipped. Please install python3-gi package 
to detect metered connections and skip downloading updates.
Starting unattended upgrades script
Allowed origins are: origin=Debian,codename=trixie,label=Debian, 
origin=Debian,codename=trixie,label=Debian-Security, 
origin=Debian,codename=trixie-security,label=Debian-Security
Initial blacklist:
Initial whitelist (not strict):
No packages found that can be upgraded unattended and no pending auto-removals
root@mail:~# ls -l /etc/apt/sources.list
-rw-r--r-- 1 root root 0 Oct 13 12:02 /etc/apt/sources.list