Fix seed for RimlessWheel/testContactGradients.
Fix seed for RimlessWheel/testContactGradients.

Resolves #303

hanssusilo/drake,astrorog/drake,edowson/drake,crogers3/drake,astrorog/drake,billhoffman/drake,manuelli/drake,astrorog/drake,psiorx/drake,scottviteri/drake,edowson/drake,thientu/drake,psiorx/drake,thientu/drake,crogers3/drake,scottviteri/drake,tkoolen/drake,crogers3/drake,manuelli/drake,thientu/drake,tkoolen/drake,sheim/drake,hanssusilo/drake,psiorx/drake,hanssusilo/drake,hanssusilo/drake,billhoffman/drake,edowson/drake,manuelli/drake,scottviteri/drake,psiorx/drake,psiorx/drake,crogers3/drake,thientu/drake,scottviteri/drake,psiorx/drake,edowson/drake,hanssusilo/drake,manuelli/drake,billhoffman/drake,scottviteri/drake,psiorx/drake,thientu/drake,tkoolen/drake,astrorog/drake,crogers3/drake,sheim/drake,thientu/drake,tkoolen/drake,astrorog/drake,hanssusilo/drake,manuelli/drake,crogers3/drake,astrorog/drake,sheim/drake,tkoolen/drake,edowson/drake,crogers3/drake,thientu/drake,sheim/drake,scottviteri/drake,billhoffman/drake,manuelli/drake,edowson/drake,tkoolen/drake,manuelli/drake,tkoolen/drake,crogers3/drake,billhoffman/drake,sheim/drake,billhoffman/drake,edowson/drake,sheim/drake,hanssusilo/drake,scottviteri/drake,sheim/drake,billhoffman/drake,hanssusilo/drake,astrorog/drake,psiorx/drake,billhoffman/drake,sheim/drake,edowson/drake