Fix location of docs source

Author: danielballan

.github/workflows/docs.yml

@@ -49,7 +49,7 @@ jobs:
           python -m pip list
 
       - name: Build HTML
-        run: sphinx-build docs docs/_build/html
+        run: sphinx-build docs/source docs/_build/html
 
       - name: Upload HTML as GitHub artifact
         uses: actions/upload-pages-artifact@v3