Always use NUnit

setup.py

@@ -34,7 +34,7 @@ setup(
     py_modules=['pytest_azurepipelines'],
     python_requires='>=3.5',
     data_files=[('resources', ['resources/style.css'])],
-    install_requires=['pytest>=5.0.0'],
+    install_requires=['pytest>=5.0.0', 'pytest-nunit>=0.5.3'],
     classifiers=[
         'Development Status :: 4 - Beta',
         'Framework :: Pytest',