Update .gitlab-ci.yml file

.gitlab-ci.yml

@@ -8,8 +8,8 @@ cache:
 pages:
   script:
     - mkdir -p cas/_build/.jupyter_cache/
-    - ln -s src cas/src
-    - ln -s data cas/data
+    - ln -s ./src cas/src
+    - ln -s ./data cas/data
     - ls -la cas
     - ls -la cas/src
     - jupyter-book build cas