remove Yahoo groups reference

Author: Vladimir Kotal

opengrok-tools/setup.py

@@ -27,7 +27,6 @@ def readme():
     url='https://github.com/OpenGrok/OpenGrok',
     license='CDDL',
     author='Oracle',
-    author_email='[email protected]',
     description='Tools for managing OpenGrok instance',
     long_description=readme(),
     python_requires='>=3.4, <4',