Update tox.ini

Author: cclauss

tox.ini

@@ -4,7 +4,7 @@
 # and then run "tox" from this directory.
 
 [tox]
-envlist = py27, py3{7,5,6,7,8,9,10,11}, lint, test, doc, clean
+envlist = py27, py3{8,9,10,11,12,13}, lint, test, doc, clean
 skip_missing_interpreters = true
 
 [testenv:test]
@@ -29,7 +29,7 @@ deps =
 commands = flake8 {toxinidir} --extend-exclude tests,docs,build,dist,venv,.venv --extend-ignore=E501
 
 [testenv:doc]
-basepython = python3
+basepython = python3.10  # pdoc3/pdoc#438
 deps =
      pdoc3
 commands = pdoc --html --force --output-dir docs filetype