Add icon / grey text when task is closed on workboards

Summary: Fixes T10281. Adds the closed icon (resolved, dupe, ect) as an attribute and makes the text grey again.

Test Plan:
View workboard with "All Tasks"

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: Korvin

Maniphest Tasks: T10281

Differential Revision: https://secure.phabricator.com/D15187