ci: update tox.ini to include python 3.13

Author: wookayin

.github/workflows/test.yml

@@ -28,6 +28,7 @@ jobs:
       fail-fast: false
       matrix:
         config: [
+          # NOTE: don't forget updating tox.ini
           { python-version: '3.13', neovim-version: 'nightly' },
           { python-version: '3.12', neovim-version: 'nightly' },
           { python-version: '3.12', neovim-version: 'stable' },

tox.ini

@@ -4,7 +4,7 @@
 [tox]
 min_version = 4.0
 envlist =
-  py{37,38,39,310,311,312}-asyncio
+  py{37,38,39,310,311,312,313}-asyncio
   checkqa
 skip_missing_interpreters =
   true
@@ -18,6 +18,7 @@ python =
   3.10: py310
   3.11: py311
   3.12: py312
+  3.13: py313
   pypy3: pypy3
 
 [testenv]