Fix circle build (pytorch#438)

I was told this line added to our config should fix the problem.

Author: JoelMarcey

.circleci/config.yml

@@ -29,7 +29,8 @@ pytorch_tutorial_build_defaults: &pytorch_tutorial_build_defaults
           linux-image-generic \
           moreutils \
           nvidia-docker2 \
-          expect-dev
+          expect-dev \
+          docker-ce=18.06.2~ce~3-0~ubuntu
 
         sudo pkill -SIGHUP dockerd