tested by running:
```
./configure --with-config=user; cp -a contrib/debian .
dpkg-buildpackage -b -uc -us
```
on a Debian 12 based system.
and checking where the completion file got installed.
Reviewed-by: Umer Saleem <usaleem@ixsystems.com>
Signed-off-by: Stoiko Ivanov <s.ivanov@proxmox.com>
Closes#15304
