chore(Dockerfile): update docker-py to 1.10.6

See https://github.com/docker/docker-py/blob/release/docs/change_log.md#1106

Author: mboersma

rootfs/Dockerfile

@@ -7,7 +7,7 @@ RUN buildDeps='gcc git libffi-dev libssl-dev python-dev python-pip python-wheel
         libffi6 \
         libssl1.0.0 \
         python && \
-	pip install --disable-pip-version-check --no-cache-dir docker-py==1.10.3 && \
+	pip install --disable-pip-version-check --no-cache-dir docker-py==1.10.6 && \
     # cleanup
     apt-get purge -y --auto-remove $buildDeps && \
     apt-get autoremove -y && \