use python 3.13 to build docs

Author: dionhaefner

.github/workflows/build_docs.yml

@@ -33,7 +33,7 @@ jobs:
       - name: Set up Python
         uses: actions/setup-python@v6
         with:
-          python-version-file: "pyproject.toml"
+          python-version: "3.13"
 
       - name: Restore UV environment
         run: cp production.uv.lock uv.lock