remove .gitlab-ci.yml

.gitlab-ci.yml

-stages:
-  - mirror
-
-gitolite_mirror:
-  stage: mirror
-  image:
-    name: alpine/git
-    entrypoint: [ "/bin/sh", "-c" ]
-  variables:
-    GIT_STRATEGY: clone
-    GIT_CHECKOUT: "false"
-  script: |
-    mkdir -p ~/.ssh
-    echo "${GITLAB_MIRROR_SERVICE}" > ~/.ssh/id_ecdsa
-    echo "${GITOLITE_SSH_FINGERPRINT}" > ~/.ssh/known_hosts
-    chmod go-rw -R ~/.ssh
-    cd /tmp
-    git clone --mirror ${CI_REPOSITORY_URL} project
-    cd project
-    git remote add gitolite git@git.ub.intern.uni-leipzig.de:gitlab-vufind.git
-    git push --mirror gitolite
-  tags: [docker]
-