[Merge] ~rcj/livecd-rootfs/+git/livecd-rootfs:bugfix/snapd_for_core18-eoan into livecd-rootfs:ubuntu/eoan

[Robert C Jennings]

I've tested this with autopkgtest and verified that an ubuntu-cpc image where lxd has just moved to base on core18 in stable will pull in core18, snapd, and lxd and will not pull in core.
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https://code.launchpad.net/~rcj/livecd-rootfs/+git/livecd-rootfs/+merge/382312
Your team Ubuntu Core Development Team is requested to review the proposed merge of ~rcj/livecd-rootfs/+git/livecd-rootfs:bugfix/snapd_for_core18-eoan into livecd-rootfs:ubuntu/eoan.