Add starting docker service for ARM instances (apache#38149)

* Add starting docker service for ARM instances

The apache#38107 switched to smaller ARM instances, and removed moving
docker service to tmpfs, but it also removed docker service starting
from the instances. As an effect cache building would be much
slower - because it would not use the remote docker builder (as
the remote docker instance was not running). MUCH slower. The
effect of it was not noticeable in the PR but full cache rebuild
would take about an hour or so.

Starting docker service on remote machine should fix it.

* Update scripts/ci/images/initialize.sh

scripts/ci/images/initialize.sh

@@ -16,6 +16,10 @@
 # specific language governing permissions and limitations
 # under the License.
 
+# Start docker service
+sudo service docker start
+
+
 # This instance will run for maximum 40 minutes and
 # It will terminate itself after that (it can also
 # be terminated immediately when the job finishes)