Add toolip to Mock History in Pholio

Summary: Fixes T8985, Adds a tooltip with the filename

Test Plan: Update a few Pholio mocks, see names when hovering

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: epriestley, Korvin

Maniphest Tasks: T8985

Differential Revision: https://secure.phabricator.com/D13746