Try to put the files inside the tar balls into sub-directories

As per this SO tip, which uses GNU tar: https://superuser.com/a/237752/513105

.gitlab-ci.yml

@@ -4,10 +4,11 @@ pages:
   stage: deploy
   script:
   - mkdir public
-  - tar czf public/pandas-tutorial-tasks.tar.gz Introduction-to-Pandas--tasks.ipynb Introduction-to-Pandas--solution.ipynb lost.json nest-data.csv
+  - tar czf public/pandas-tutorial-tasks.tar.gz --transform 's,^,pandas-tutorial-tasks/,' Introduction-to-Pandas--tasks.ipynb Introduction-to-Pandas--solution.ipynb lost.json nest-data.csv
+  - tar czf public/pandas-tutorial-tasks--jureca.tar.gz --transform 's,^,pandas-tutorial-tasks/,' Introduction-to-Pandas--JURECA--tasks.ipynb Introduction-to-Pandas--JURECA--solution.ipynb lost.json nest-data.csv
   - cp Introduction-to-Pandas--slides.ipynb public/
   - cp Introduction-to-Pandas--slides.pdf public/
-  - tar czf public/pandas-tutorial-slides.tar.gz Introduction-to-Pandas--slides.html custom.css custom.js fzj.js img/ reveal.js/
+  - tar czf public/pandas-tutorial-slides.tar.gz  --transform 's,^,pandas-tutorial-slides/,' Introduction-to-Pandas--slides.html custom.css custom.js fzj.js img/ reveal.js/
   - git checkout -f pages
   - cp index.html public/
   artifacts: