Update for modern Python compatibility

setup.py

@@ -1,64 +1,9 @@
+"""Minimal setup.py for backward compatibility.
+
+Modern installation should use pyproject.toml with pip >= 21.3
+"""
+
 from setuptools import setup
-from setuptools import find_packages
 
-version = "0.2.0"
-
-install_requires = [
-    "acme>=0.29.0",
-    "certbot>=0.34.0",
-    "setuptools",
-    "requests",
-    "mock",
-    "requests-mock",
-    "dns-lexicon"
-]
-
-# read the contents of your README file
-from os import path
-
-this_directory = path.abspath(path.dirname(__file__))
-with open(path.join(this_directory, "README.rst")) as f:
-    long_description = f.read()
-
-setup(
-    name="certbot-dns-corenetworks",
-    version=version,
-    description="Core Networks DNS Authenticator plugin for Certbot",
-    long_description=long_description,
-    long_description_content_type="text/x-rst",
-    url="https://github.com/MasinAD/certbot-dns-corenetworks",
-    author="Masin Al-Dujaili",
-    author_email="masin.aldujaili@googlemail.com",
-    license="Apache License 2.0",
-    python_requires=">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*",
-    classifiers=[
-        "Development Status :: 3 - Alpha",
-        "Environment :: Plugins",
-        "Intended Audience :: System Administrators",
-        "License :: OSI Approved :: Apache Software License",
-        "Operating System :: POSIX :: Linux",
-        "Programming Language :: Python",
-        "Programming Language :: Python :: 2",
-        "Programming Language :: Python :: 2.7",
-        "Programming Language :: Python :: 3",
-        "Programming Language :: Python :: 3.4",
-        "Programming Language :: Python :: 3.5",
-        "Programming Language :: Python :: 3.6",
-        "Programming Language :: Python :: 3.7",
-        "Topic :: Internet :: WWW/HTTP",
-        "Topic :: Security",
-        "Topic :: System :: Installation/Setup",
-        "Topic :: System :: Networking",
-        "Topic :: System :: Systems Administration",
-        "Topic :: Utilities",
-    ],
-    packages=find_packages(),
-    include_package_data=True,
-    install_requires=install_requires,
-    entry_points={
-        "certbot.plugins": [
-            "dns-corenetworks = certbot_dns_corenetworks.dns_corenetworks:Authenticator"
-        ]
-    },
-    test_suite="certbot_dns_corenetworks",
-)
+# All configuration is now in pyproject.toml
+setup()