Force black formatting

Black removes the burden of manual code formatting and is by now
considered the standard Python formatting tool.

https://black.readthedocs.io/en/stable/

Format all Python code with black.

GitHub linting action is updated to ensure all files are formatted with
Black.

Signed-off-by: Piotr Husiatyński <phusiatynski@gmail.com>

setup.py

@@ -2,15 +2,15 @@ import os
 from setuptools import setup
 
 try:
-    readme = open(os.path.join(os.path.dirname(__file__), 'README.md')).read()
+    readme = open(os.path.join(os.path.dirname(__file__), "README.md")).read()
 except:
-    readme = ''
+    readme = ""
 
 setup(
-    name='podman-compose',
+    name="podman-compose",
     description="A script to run docker-compose.yml using podman",
     long_description=readme,
-    long_description_content_type='text/markdown',
+    long_description_content_type="text/markdown",
     classifiers=[
         "Programming Language :: Python",
         "Programming Language :: Python :: 3",
@@ -23,21 +23,17 @@ setup(
         "Topic :: Software Development :: Build Tools",
         "License :: OSI Approved :: GNU General Public License v2 (GPLv2)",
     ],
-    keywords='podman, podman-compose',
-    author='Muayyad Alsadi',
-    author_email='alsadi@gmail.com',
-    url='https://github.com/containers/podman-compose',
-    py_modules=['podman_compose'],
-    entry_points={
-        'console_scripts': [
-            'podman-compose = podman_compose:main'
-        ]
-    },
+    keywords="podman, podman-compose",
+    author="Muayyad Alsadi",
+    author_email="alsadi@gmail.com",
+    url="https://github.com/containers/podman-compose",
+    py_modules=["podman_compose"],
+    entry_points={"console_scripts": ["podman-compose = podman_compose:main"]},
     include_package_data=True,
-    license='GPL-2.0-only',
+    license="GPL-2.0-only",
     install_requires=[
-        'pyyaml',
-        'python-dotenv',
+        "pyyaml",
+        "python-dotenv",
     ],
     # test_suite='tests',
     # tests_require=[