Adapt Python version in tox to build docs to match the one in RTD config

Author: jugmac00

tox.ini

@@ -65,7 +65,7 @@ python =
 [testenv:docs]
 description = generate docs in HTML format
 # specifying the exact python version as in .readthedocs.yaml for compatibility
-basepython = python3.11 
+basepython = python3.12
 deps = -r docs/requirements.txt
 commands = sphinx-build -b html docs _build/html