message: [cluster-test] Login to ECR before docker pull
  Also propagate error code if cluster test runner fails
  Closes:
  Approved by: ankushagarwal
diff: @@ -18,6 +18,8 @@ while (( "$#" )); do
  shift 1
  ;;
  -i|--image)
  + echo "Logging in to ECR repo"
  + $(aws ecr get-login --no-include-email --region us-west-2)
  DOCKER_IMAGE=$2
  shift 2
  ;;
  @@ -48,4 +50,4 @@ VARS="-e SLACK_LOG_URL -e SLACK_CHANGELOG_URL"
  # This could in theory fail due to concurrency, but it seem unlikely
  docker run $VARS -v /libra_rsa:/libra_rsa --name $CONTAINER --rm $DOCKER_IMAGE $* &
  -wait
  +wait $!
  