debt: test pypy311 and drop pypy39

Author: kieran-ryan

.github/workflows/test-python.yml

@@ -28,7 +28,7 @@ jobs:
           - { os: 'windows-latest', python-version: '3.13' }
           - { os: 'macos-latest', python-version: '3.13' }
         os: ['ubuntu-latest']
-        python-version: ['3.9', '3.10', '3.11', '3.12', '3.13', 'pypy3.9', 'pypy3.10']
+        python-version: ['3.9', '3.10', '3.11', '3.12', '3.13', 'pypy3.10', 'pypy3.11']
     defaults:
       run:
         working-directory: python

python/pyproject.toml

@@ -80,7 +80,7 @@ extend-select = [
 "src/cucumber_messages/__init__.py" = ["F403"]
 
 [tool.tox]
-env_list = ["lint", "3.13", "3.12", "3.11", "3.10", "3.9", "pypy310", "pypy39"]
+env_list = ["lint", "3.13", "3.12", "3.11", "3.10", "3.9", "pypy311", "pypy310"]
 requires = ["tox>=4.22"]
 
 [tool.tox.env.lint]