Continue after rejecting commits from a commit query

Summary: Fixes T6880. If matching commits have no visible/loadable repository, we shouldn't keep going forward in the loop.

Test Plan: Havne't built a repro locally yet so not 100% sure this fixes it.

Reviewers: btrahan, mbishopim3, fabe

Reviewed By: mbishopim3, fabe

Subscribers: mbishopim3, epriestley

Maniphest Tasks: T6880

Differential Revision: https://secure.phabricator.com/D11251