Minor change to PhutilInfrastructureTestCase

Summary: Update PhutilInfrastructureTestCase after D9860 and D9861.

Test Plan: arc unit should do the trick.

Reviewers: epriestley, Blessed Reviewers

Reviewed By: epriestley, Blessed Reviewers

Subscribers: epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D9862