Make it more visually clear that you can click things in the "Big List of Clickable Things" UI element

Summary:
Ref T13259. An install provided feedback that it wasn't obvious you could click the buttons in this UI.

Make it more clear that these are clickable buttons.

Test Plan:
{F6251585}

{F6251586}

Reviewers: amckinley

Reviewed By: amckinley

Maniphest Tasks: T13259

Differential Revision: https://secure.phabricator.com/D20238