Update .gitlab-ci.yml

.gitlab-ci.yml

-
-image: python:3.7.1-slim
+# This file is a template, and might need editing before it works on your project.
+# Full project: https://gitlab.com/pages/plain-html
 pages:
-    script:
-        - pip install mkdocs
-        - pip install mkdocs-material
-        - mkdocs --version
-        - mkdocs build
-    artifacts:
-        paths:
-            - public
-    tags:
-        - general
+  stage: deploy
+  script:
+  - mkdir .public
+  - cp -r * .public
+  - mv .public public
+  artifacts:
+    paths:
+    - public
+  only:
+  - master
\ No newline at end of file