chore: Add extra requirements for test purposes

Author: mgappa

pyproject.toml

@@ -1,3 +1,6 @@
 [build-system]
 requires = ["setuptools"]
-build-backend = "setuptools.build_meta"
+build-backend = "setuptools.build_meta"
+
+[project.optional-dependencies]
+test = ["coverage==7.6.10", "responses==0.25.3"]

setup.py

@@ -34,5 +34,8 @@
         'requests',
         'update_checker'
     ],
+    extras_require={
+        'test': ['coverage==7.6.10', 'responses==0.25.3']
+    },
     python_requires='>=3.6'
 )