update tox configuration

tox.ini

@@ -9,37 +9,43 @@ filterwarnings =
 
 [gh-actions]
 python =
-    3.6: py36
-    3.7: py37
-    3.8: py38, lint, docs
+    3.8: py38
+    3.9: py39
+    3.10: py310
+    3.11: py311
+    3.12: py312, lint, docs
+    3.13: py313
 
 
 [tox]
 envlist =
        lint
-       {py36,py37}-django2.2-drf3.11
-       {py36,py37,py38}-django3.0-drf3.11
+       {py38,py39,py310}-django3.2-drf3.15.1
+       {py38,py39,py310,py311,py312}-django4.2-drf3.15.2
+       {py310,py311,py312,py313}-django5.0-drf3.15.2
        docs
 isolated_build = True
 
 
 [testenv]
 commands = pytest {posargs}
 deps =
-       django2.2: Django==2.2.*
-       django3.0: Django==3.0.*
-       drf3.11: djangorestframework==3.11.*
+       django3.2: django==3.2.*
+       django4.2: django==4.2.*
+       django5.0: django==5.0.*
+       drf3.15.1: djangorestframework==3.15.1
+       drf3.15.2: djangorestframework==3.15.*
        pytest-django
 
 
 [testenv:lint]
-basepython = python3.8
+basepython = python3.12
 extras = dev
 passenv = HOMEPATH  # needed on Windows
 commands = pre-commit run --all-files
 
 
 [testenv:docs]
-basepython = python3.8
+basepython = python3.12
 extras = docs
 commands = mkdocs build