[Redesign] Add ActionIcon to home panels

Summary: Ref T8099, adds an action icon similar to dashboards for taking people to the search.

Test Plan: Click on each icon, verify it takes me to correct URL.

Reviewers: btrahan, epriestley

Reviewed By: epriestley

Subscribers: Korvin, epriestley

Maniphest Tasks: T8099

Differential Revision: https://secure.phabricator.com/D12974