Don't show an auth provider as enabled if it's still being created

Test Plan: attempted to create a new auth provider; observed that "enabled" ui element does not render. viewed existing auth provider and observed that "enabled" ui element still renders

Reviewers: #blessed_reviewers, epriestley

Reviewed By: #blessed_reviewers, epriestley

Subscribers: Korvin

Maniphest Tasks: T12245

Differential Revision: https://secure.phabricator.com/D17337