fix: dev: update action/python versions, packaging, and tox file

* add workaround for py39 on macos installed with broken setuptools

Signed-off-by: Stephen L Arnold <sarnold@vctlabs.com>

Author: sarnold

setup.py

@@ -0,0 +1,47 @@
+#! /usr/bin/env python
+from setuptools import setup
+import cpplint
+
+# some pip versions bark on comments
+def read_without_comments(filename):
+    with open(filename) as f:
+        return [line for line in f.read().splitlines() if not len(line) == 0 and not line.startswith('#')]
+
+
+setup(name='cpplint',
+      version=cpplint.__VERSION__,
+      py_modules=['cpplint'],
+      # generate platform specific start script
+      entry_points={
+          'console_scripts': [
+              'cpplint = cpplint:main'
+          ]
+      },
+      install_requires=[],
+      url='https://github.com/cpplint/cpplint',
+      download_url='https://github.com/cpplint/cpplint',
+      keywords=['lint', 'python', 'c++'],
+      maintainer='cpplint Developers',
+      classifiers=['Development Status :: 5 - Production/Stable',
+                   'Environment :: Console',
+                   'Intended Audience :: End Users/Desktop',
+                   'License :: Freely Distributable',
+                   'License :: OSI Approved :: BSD License',
+                   'Natural Language :: English',
+                   'Programming Language :: Python :: 3 :: Only',
+                   'Programming Language :: Python :: 3.9',
+                   'Programming Language :: Python :: 3.10',
+                   'Programming Language :: Python :: 3.11',
+                   'Programming Language :: Python :: 3.12',
+                   'Programming Language :: Python :: 3.13',
+                   'Programming Language :: C++',
+                   'Topic :: Software Development :: Quality Assurance'],
+      description='Automated checker to ensure C++ files follow Google\'s style guide',
+      long_description=open('README.rst').read(),
+      long_description_content_type='text/x-rst',
+      license='BSD-3-Clause',
+      # extras_require allow pip install .[dev]
+      extras_require={
+          'test': read_without_comments('test-requirements'),
+          'dev': read_without_comments('dev-requirements'),
+      })

tox.ini

@@ -94,4 +94,4 @@ deps =
     pip>=21.1
 
 commands =
-    bash -c 'rm -rf build/ dist/ __pycache__/ *.egg-info/'
+    bash -c 'rm -rf build/ dist/ __pycache__/ *.egg-info/ .coverage'