[Merge] livecd-rootfs:sil2100/backport-datasource-raspi3 into livecd-rootfs:ubuntu/bionic

[Dave Jones]

Review: Approve

Looks good to me, especially the removal of the awful dpkg detection hack (which wouldn't have been specific enough for the pi2 image anyway).

I initially queried the rationale of leaving the cloud-init seed on the root partition for the "+raspi2" image when the "+raspi3" images will now have their seed on the boot partition. However, given Łukasz's reasoning that the "+raspi2" image is essentially continuity-only and is discouraged from use for *new* installations, it makes sense to keep the image as unchanged as possible (which also implies the cloud-init seed itself shouldn't be updated either).
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https://code.launchpad.net/~ubuntu-core-dev/livecd-rootfs/+git/livecd-rootfs/+merge/374593
Your team Ubuntu Core Development Team is requested to review the proposed merge of livecd-rootfs:sil2100/backport-datasource-raspi3 into livecd-rootfs:ubuntu/bionic.