Update .gitlab-ci.yml

.gitlab-ci.yml

-# This file is a template, and might need editing before it works on your project.
-# Full project: https://gitlab.com/pages/plain-html
+image: 
+  name: astefanutti/decktape
+  entrypoint: [""]
+
+stages:
+  - documentation
+  - deploy
+
+pdf:
+  stage: documentation
+  script: 
+     - node /decktape/decktape.js --chrome-path chromium-browser --chrome-arg=--no-sandbox remark prez.html pres.pdf
+  artifacts:
+    paths:
+     - pres.pdf
+
+
 pages:
   stage: deploy
   script: