Revert the Sphinx upgrade

Signed-off-by: tdruez <[email protected]>

Author: tdruez

pyproject.toml

@@ -105,7 +105,7 @@ dev = [
   # Debug
   "django-debug-toolbar==5.2.0",
   # Documentation
-  "Sphinx==8.2.3",
+  "Sphinx==8.1.3",  # Newer versions dropped Python 3.10 support
   "sphinx-rtd-theme==3.0.2",
   "sphinx-rtd-dark-mode==1.3.0",
   "sphinxcontrib-django==2.5",