'redshift' tag is no longer used

And is currently assigned to host not supporting docker

Set 'docker' tag

.gitlab-ci.yml

@@ -8,7 +8,7 @@ before_script:
 
 test_build_image:
   tags:
-  - redshift
+  - docker
   script:
     - docker build .
   except:
@@ -16,7 +16,7 @@ test_build_image:
 
 build_image:
   tags:
-  - redshift
+  - docker
   script:
     - docker pull $CI_REGISTRY_IMAGE:$CI_BUILD_TAG || true
     - docker build --cache-from $CI_REGISTRY_IMAGE:$CI_BUILD_TAG --pull -t "$CI_REGISTRY_IMAGE:$CI_BUILD_TAG" .