When there are no setup issues, don't show a weird empty box

Summary: Ref T13189. When there are no setup issues, we currently double-render a weird setup issues box underneath the notice. Get rid of it.

Test Plan: Viewed page with and without setup issues, saw less awkward UI.

Reviewers: amckinley

Maniphest Tasks: T13189

Differential Revision: https://secure.phabricator.com/D19609