mq: fix failing qrefresh test Additions to test-mq-qrefresh.t in f08df4d38442 (mq: ignore subrepos (issue2499)) were originally based on a version prior to d0e21c5fde41 (subrepo: handle missing subrepo spec file as removed). This fixes a test failure that resulted from the former being applied after the latter, noticed by abuehl.