Fix unreliable child.exitstatus being set in git command execution
Fix unreliable child.exitstatus being set in git command execution

Adding a child.close() will guarantee that child.exitstatus will be set
properly.

Also add the raise exception back in.

nickzuber/ClusterRunner,josephharrington/ClusterRunner,Medium/ClusterRunner,box/ClusterRunner,Medium/ClusterRunner,box/ClusterRunner,nickzuber/ClusterRunner,josephharrington/ClusterRunner