Merge pull request #2540 from VWS-Python/dependabot/pip/sphinx-toolbox-3.9.0

Bump sphinx-toolbox from 3.8.3 to 3.9.0

Author: adamtheturtle

pyproject.toml

@@ -93,7 +93,7 @@ optional-dependencies.dev = [
     "sphinx-paramlinks==0.6",
     "sphinx-pyproject==0.3.0",
     "sphinx-substitution-extensions==2025.3.3",
-    "sphinx-toolbox==3.8.3",
+    "sphinx-toolbox==3.9.0",
     "sphinxcontrib-httpdomain==1.8.1",
     "sphinxcontrib-spelling==8.0.1",
     "sybil==9.1.0",