Highlight uncommitted changes in version

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.

test/integration/docker/deployer/Dockerfile

@@ -23,7 +23,6 @@ RUN mkdir -p /etc/docker/certs.d/registry:4443 && ln -s /shared/certs/domain.crt
 RUN git config --global user.email "deployer@example.com"
 RUN git config --global user.name "Deployer"
 RUN git init && git add . && git commit -am "Initial version"
-RUN git rev-parse HEAD > version
 
 HEALTHCHECK --interval=1s CMD pgrep sleep