Use uv for installing Zensical

Author: pinkwah

.github/workflows/docs.yml

@@ -20,7 +20,8 @@ jobs:
       - uses: actions/setup-python@v6
         with:
           python-version: 3.x
-      - run: pip install zensical
+      - uses: astral-sh/setup-uv@v5
+      - run: uv sync
       - run: zensical build --clean
       - uses: actions/upload-pages-artifact@v5
         with: