[Merge] ~toabctl/livecd-rootfs:boot-partition into livecd-rootfs:ubuntu/master

[Philip Roche]

Review: Needs Information

I am nervous making this change so close to mantic release as the fall out is unknown.

This nervousness is prompted by the fall out of the minimal seed changes being merged in to mantic before they were fully tested. 

I would be much happier if we had tested for each cloud/and download for base and minimal before merging - just like toabctl has done now for AWS.
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https://code.launchpad.net/~toabctl/livecd-rootfs/+git/livecd-rootfs-1/+merge/451330
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