[Merge] ~xnox/livecd-rootfs:snap-preseed-with-channel into livecd-rootfs:ubuntu/master

[Dimitri John Ledkov]

This is of interest to forexample specify a different track for the seeded LXD snap, to use 4.0/stable/ubuntu-20.04.
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https://code.launchpad.net/~xnox/livecd-rootfs/+git/livecd-rootfs/+merge/385064
Your team Ubuntu Core Development Team is requested to review the proposed merge of ~xnox/livecd-rootfs:snap-preseed-with-channel into livecd-rootfs:ubuntu/master.