Corrige le job de build de l'image Docker.

.gitlab-ci.yml

@@ -32,10 +32,8 @@ docker-image:
     PREZBUILDER_IMAGE: "${CI_REGISTRY_IMAGE}"
     PREZBUILDER_TAG: "${CI_COMMIT_REF_NAME}"
   script:
-    - set -x
-    - docker pull "${IMAGE}" || exit 0
-    - docker build --cache-from "${IMAGE}" --tag "${IMAGE}" .
-    - bash -x bin/prezbuilder-docker build src public
+    - docker build --tag "${IMAGE}" .
+    - bin/prezbuilder-docker build src public
     - "[ -e public/index.html ]"
     - docker push "${IMAGE}"