fix ircrobots.matching not being packaged

setup.py

@@ -1,4 +1,4 @@
-import setuptools
+from setuptools import find_namespace_packages, setup
 
 with open("README.md", "r") as fh:
     long_description = fh.read()
@@ -7,7 +7,7 @@ with open("VERSION", "r") as version_file:
 with open("requirements.txt", "r") as requirements_file:
     install_requires = requirements_file.read().splitlines()
 
-setuptools.setup(
+setup(
     name="ircrobots",
     version=version,
     author="jesopo",
@@ -16,7 +16,7 @@ setuptools.setup(
     long_description=long_description,
     long_description_content_type="text/markdown",
     url="https://github.com/jesopo/ircrobots",
-    packages=["ircrobots"],
+    packages=["ircrobots"] + find_namespace_packages(include=["ircrobots.*"]),
     package_data={"ircrobots": ["py.typed"]},
     classifiers=[
         "Programming Language :: Python :: 3",