Snapcraft doesn't always copy the host's version into the VM

[Ken VanDine]

Periodically snapcraft will fail to build because the version of snapcraft gets refreshed in the VM to the stable channel rather than copying snapcraft from the host.

Launching a VM.
snapd 2.43.3 from Canonical✓ refreshed
Issues while validating snapcraft.yaml: The 'apps/snap-store/extensions[0]' property does not match the required schema: 'gnome-3-34' is not one of ['gnome-3-28', 'kde-neon']
snapcraft-snap-store # snap info snapcraft
name: snapcraft
summary: easily create snaps
publisher: Canonical✓
store-url: https://snapcraft.io/snapcraft
contact: https://forum.snapcraft.io/c/snapcraft
license: GPL-3.0
description: |
  Package, distribute, and update any app for Linux and IoT.

  Snaps are containerised software packages that are simple to create and install. They auto-update
  and are safe to run. And because they bundle their dependencies, they work on all major Linux
  systems without modification.
commands:
  - snapcraft
snap-id: vMTKRaLjnOJQetI78HjntT37VuoyssFE
refresh-date: today at 08:25 CET
channels:
  stable: 3.10 2020-03-03 (4126) 62MB classic
  candidate: ↑
  beta: ↑
  edge: 3.10+git12.g51bd8359 2020-03-02 (4176) 62MB classic
installed: 3.10 (4126) 62MB classic