Delete unnecessary dependency on argparse

argparse is part of Python's build-in modules, so there is no need for
an external dependency.

Fixes issue #8

setup.py

@@ -28,7 +28,7 @@ setup(
     author='Dr. Meta',
     description='This is a meta package to install the automatically generated NET-API 3.0, 3.1 and 3.2 definitions.',
     url='https://git.scc.kit.edu/scc-net/net-suite/netdb-client-lib',
-    install_requires=['argparse', 'requests'],
+    install_requires=['requests'],
     python_requires='>=3.7',
     packages=['netdb_client'],
     cmdclass={'build_py': APIGenBuild}