[Merge] ~mwhudson/livecd-rootfs/+git/livecd-rootfs:no-snaps-ubuntu-cpc-minimized into livecd-rootfs:ubuntu/master

[Tobias Koch]

I put the proposed modifcations in

https://code.launchpad.net/~tobijk/livecd-rootfs/+git/livecd-rootfs/+merge/365878

which is rebased against ubuntu/master, because it needs a more recent snap-tool. It seems work as expected, but I haven't yet fully verified it. It also does not cover the special case where we have only core18 snaps in an image (see also

https://bugs.launchpad.net/ubuntu/+source/livecd-rootfs/+bug/1820840/comments/3

action point #2).
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https://code.launchpad.net/~mwhudson/livecd-rootfs/+git/livecd-rootfs/+merge/364222
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