tox.ini: update Python interpreters in envlist

Python 3.7 and earlier are now EOL, and 3.11 is the latest.

Author: aspiers

.travis.yml

@@ -3,10 +3,14 @@ virt: lxd
 language: python
 matrix:
   include:
-  - python: 3.7
-    env: TOX_ENV=py37
   - python: 3.8
     env: TOX_ENV=py38
+  - python: 3.9
+    env: TOX_ENV=py39
+  - python: 3.10
+    env: TOX_ENV=py39
+  - python: 3.11
+    env: TOX_ENV=py311
 install:
 - pip install tox
 script:

tox.ini

@@ -3,7 +3,7 @@
 
 [tox]
 minversion = 1.8
-envlist = py37,py38,flake8
+envlist = py38,py39,py310,py311,flake8
 skip_missing_interpreters = True
 
 [testenv]