Remove unused import in reviews_for_bugs.
Remove unused import in reviews_for_bugs.

Change-Id: I9fbeafe8badc30dea606f63622f80b4713570307

cp16net/reviewstats,JohnGarbutt/reviewstats,openstack-infra/reviewstats,JohnGarbutt/reviewstats,cp16net/reviewstats,openstack-infra/reviewstats