Add PAT token environment variable to documentation update workflow

- Include PAT_TOKEN as an environment variable in the GitHub Actions workflow
- Prepare for potential authentication or access requirements in the documentation update process

Author: Chivier

.github/workflows/update_docs.yml

@@ -18,6 +18,8 @@ jobs:
         with:
           python-version: '3.8'
 
+      - env:
+          PAT_TOKEN: ${{ secrets.PAT_TOKEN }}
       # Install Pandoc using apt-get
       - run: |
           sudo apt-get update
@@ -47,4 +49,4 @@ jobs:
           git config user.name "Chivier"
           git config user.email "[email protected]"
           git commit -m 'update docs'
-          git push -u origin main
+          git push https://[email protected]/openmlsys/html-en.git HEAD:main