Remove old setup.py test pytest invocation

See also:
- http://doc.pytest.org/en/5.3.2/changelog.html#pytest-3-6-2-2018-06-20
- pytest-dev/pytest#3552

Author: tony

setup.py

@@ -1,11 +1,8 @@
 #!/usr/bin/env python
 # -*- coding: utf-8 -*-
-
 import os
 import sys
 
-from setuptools.command.test import test as TestCommand
-
 try:
     from setuptools import setup
 except ImportError:
@@ -31,20 +28,6 @@
     sys.exit()
 
 
-class PyTest(TestCommand):
-    user_options = [('pytest-args=', 'a', "Arguments to pass to py.test")]
-
-    def initialize_options(self):
-        TestCommand.initialize_options(self)
-        self.pytest_args = []
-
-    def run_tests(self):
-        import pytest
-
-        errno = pytest.main(self.pytest_args)
-        sys.exit(errno)
-
-
 readme = open('README.rst').read()
 
 setup(
@@ -58,7 +41,6 @@ def run_tests(self):
     include_package_data=True,
     install_requires=install_reqs,
     tests_require=tests_reqs,
-    cmdclass={'test': PyTest},
     license="MIT",
     zip_safe=False,
     keywords=[