CI: update actions

Author: rhaschke

.github/workflows/ci.yaml

@@ -121,7 +121,7 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v4
       - name: Setup Pages
-        uses: actions/configure-pages@v2
+        uses: actions/configure-pages@v5
 
       - name: Install dependencies
         run: |
@@ -146,7 +146,7 @@ jobs:
           sphinx-build -W -b linkcheck core/doc _site
 
       - name: Upload pages artifact
-        uses: actions/upload-pages-artifact@v1
+        uses: actions/upload-pages-artifact@v3
 
   # Deployment job
   deploy:
@@ -159,4 +159,4 @@ jobs:
     steps:
       - name: Deploy to GitHub Pages
         id: deployment
-        uses: actions/deploy-pages@v1
+        uses: actions/deploy-pages@v4