GitLab

Shrink the cloud image to the bare minimum (2GB)

cloud-init resizes the disk[1] so we don't need a "big disk" with a lot
of unused space + some cloud providers charges for the unused space +
some cloud providers offers VM with disk < 20GB.

[1] https://cloudinit.readthedocs.io/en/latest/topics/modules.html#growpart

Fix #127

Expand the basic disk image from 20G -> 40G

It is meant for local usage so the disk should be "big enough".