Do not crash list-targets if one target is bad
Do not crash list-targets if one target is bad

Summary:
If idb cant describe one target, we should not crash the entire list-targets command

Should we even disconnect it if we can't describe it?

Reviewed By: zeyadsalloum

Differential Revision: D17160908

fbshipit-source-id: 891bf18e31894eff5a01f00c558053c115e0eb94

facebook/FBSimulatorControl,facebook/FBSimulatorControl,facebook/FBSimulatorControl,facebook/FBSimulatorControl,facebook/FBSimulatorControl