Update .gitlab-ci.yml file

.gitlab-ci.yml

+image: mkdocs:imgw
+
+stages:
+    - build
+    - deploy
+
+Build:
+    stage: build
+    tags:
+        - dev
+    script:
+        - mkdocs build
+
+Deploy:
+    stage: deploy
+    tags:
+        - dev
+    script:
+        - sshpass -p "$WOLKE_PASSWORD" scp -r /tmp/cr-site/ $WOLKE_USER@wolke.img.univie.ac.at:/var/www/html/