simpleclient.py: Use #auto tag on dependencies when use_apt_resolver is True.

[mtwebster]

This should get them marked auto-installed even though we're explicitly adding them to the package list.

ref: linuxmint/mintupdate#938

[randomnoise]

This change works for installation for kernel releases. Before installing the new kernel release version linux-generic=6.8.0-90.91, I patched this commit to check if the newly installed packages are marked as automatic.

Before:

$ apt-mark showauto | grep -i "^linux-"
$

After new kernel version installation:

$ apt-mark showauto | grep -i "^linux-"
linux-headers-6.8.0-90
linux-headers-6.8.0-90-generic
linux-image-6.8.0-90-generic
linux-modules-6.8.0-90-generic
linux-modules-extra-6.8.0-90-generic
linux-tools-6.8.0-90
linux-tools-6.8.0-90-generic
$

Version-specific kernel packages are marked as automatic, and apt autoremove will remove them according to its rules. This should fix the issue of automatic removal of older kernel versions 🎉

Thanks @mtwebster