chore: remove obsolete scripts from generated code (#2489)

Author: parthea

gapic/ads-templates/scripts/fixup_%name_%version_keywords.py.j2

@@ -57,9 +57,6 @@ setuptools.setup(
     setup_requires=[
         'libcst >= 0.2.5',
     ],
-    scripts=[
-        'scripts/fixup_{{ api.naming.versioned_module_name }}_keywords.py',
-    ],
     classifiers=[
         release_status,
         "Intended Audience :: Developers",