fix(google-auth-httplib2): Drop support for Python 3.7, 3.8, and 3.9#16937

parthea merged 5 commits intomaingoogleapis/google-cloud-python:mainfrom

feat/drop-python-3.7-3.9-google-auth-httplib2googleapis/google-cloud-python:feat/drop-python-3.7-3.9-google-auth-httplib2Copy head branch name to clipboard