Restored main branch as default.

Signed-off-by: Cristiano Urban <cristiano.urban@inaf.it>

.gitlab-ci.yml

@@ -10,7 +10,7 @@ variables:
   tags:
     - shell
   only:
-    - pasture
+    - master
   script:
     - docker login -u "${CI_REGISTRY_USER}" -p "${CI_REGISTRY_PASSWORD}" "${CI_REGISTRY}"
     - docker build -t "${CI_REGISTRY_IMAGE}/${IMAGE_NAME}" ${IMAGE_NAME}