If there are uncommitted changes in the app repository when building,
then append `_uncommitted_<random>` to it to distinguish the image
from one built from a clean checkout.
Also change the version used when renaming a container on redeploy to
distinguish and explain the version suffixes.
In the image prune command --all overrides --dangling=true. This removes
the image git sha image tag for the latest image which prevented
us from rolling back to it.
I've updated the integration test to now test deploy, redeploy and
rollback.