Fix building with docker-in-docker and TLS enabled with gitlab-ci

.gitlab-ci.yml

@@ -54,9 +54,13 @@ test:
   stage: deploy
   tags:
     - dockerex
-  image: docker:latest
+  # see https://docs.gitlab.com/ee/ci/docker/using_docker_build.html#tls-enabled
+  # for image usage and settings for building with TLS and docker in docker
+  image: docker:19.03.1
   services:
-    - docker:dind
+    - docker:19.03.1-dind
+  variables:
+    DOCKER_TLS_CERTDIR: "/certs"
   script:
     - DOCKER_TAG_NAME=$(echo $CI_COMMIT_REF_SLUG- | sed 's/^master-$//')
     - docker build --pull -t titan-ccp-exp-bigdata19-bridge ./exp-bigdata19-bridge