docs: modify cp command

.gitlab-ci.yml

@@ -10,7 +10,7 @@ pages:
   image: python:3.9-slim
   script:
     - mkdir .public
-    - cp -r docs/source/_build/html/ .public
+    - cp -r docs/source/_build/html/. .public
     - rm -rf public
     - mv .public public
   artifacts: