Tests: use Python 3.13 for some CI tests

Change-Id: I3c48f65f3377dbbf44f7e8dfeb2ca0bec9f1e82f
Signed-off-by: Xqt <info@gno.de>

Author: xqt

tox.ini

@@ -19,6 +19,7 @@ basepython =
     py310: python3.10
     py311: python3.11
     py312: python3.12
+    py313: python3.13
     pypy: pypy3
 setenv =
     VIRTUAL_ENV={envdir}
@@ -68,7 +69,7 @@ commands =
     pytest --mypy -m mypy pywikibot
 
 [testenv:commit-message]
-basepython = python3.8
+basepython = python3.9
 deps = commit-message-validator
 commands = commit-message-validator
 
@@ -91,15 +92,15 @@ deps =
 commands = {posargs}
 
 [testenv:doc]
-basepython = python3.12
+basepython = python3.13
 commands =
     sphinx-build -M html ./docs ./docs/_build -j auto
 deps =
     -rrequirements.txt
     -rdocs/requirements.txt
 
 [testenv:rstcheck]
-basepython = python3.12
+basepython = python3.13
 commands =
     rstcheck --version
     rstcheck --report-level WARNING -r .
@@ -108,7 +109,7 @@ deps =
     -rdocs/requirements.txt
 
 [testenv:sphinx]
-basepython = python3.12
+basepython = python3.13
 commands =
     sphinx-build -M html ./docs ./docs/_build -j auto -D html_theme=nature
 deps =