Add setup for GitHub Pages in workflow

Author: siboles

.github/workflows/sphinx-build.yml

@@ -25,6 +25,9 @@ jobs:
       - name: Install dependencies
         run: |
           pip install . --group dev
+      - name: Setup Pages
+        id: pages
+        uses: actions/configure-pages@v5
       - name: Sphinx build
         run: |
           sphinx-build docs _build