Fix a typo in docker_puppet_apply.sh

In change Icf4a64ed76635e39bbb34c3a088c55e1f14fddca we did a refactoring
of the puppet apply commmands into a single script. A typo slipped in
where we set FACTOR_uuid instead of FACTER_uuid

Change-Id: If67d1bbf50d4fdaffa14e197dffc90f5b1577712
Closes-Bug: #1750000
(cherry picked from commit dc811f803a)

docker/services/containers-common.yaml

@@ -65,7 +65,7 @@ outputs:
             cp -a /tmp/puppet-etc/* /etc/puppet || true
           fi
           echo "{\"step\": ${STEP}}" > /etc/puppet/hieradata/docker.json
-          export FACTOR_uuid=docker
+          export FACTER_uuid=docker
           set +e
           puppet apply $EXTRA_ARGS \
               --verbose \