SSL error from OSP7 director python clients: Missing subjectAltName

Issue

• Every time an OpenStack CLI is used, the following error message is displayed:

/usr/lib/python2.7/site-packages/requests/packages/urllib3/connection.py:251: SecurityWarning: Certificate has no `subjectAltName`, falling back to check for a `commonName` for now. This feature is being removed by major browsers and deprecated by RFC 2818. (See https://github.com/shazow/urllib3/issues/497 for details.)
  SecurityWarning

• This error will be displayed when the director is configured to use SSL encryption (see undercloud documentation for more information)

undercloud_service_certificate=/etc/pki/instack-certs/undercloud.pem