prevents a goroutine from being leaked if binary cmd fails to finish

[hex0punk]

Prevents an egde case where a goroutine would be leaked when the following case executes

		case <-time.After(binaryCmdWaitTimeout):
			log.G(ctx).Errorf("timeout while waiting for binaryIO process to finish. Killing")
			err := b.cmd.Process.Kill()
			if err != nil {
				log.G(ctx).WithError(err).Errorf("error while killing binaryIO process")
			}
		}

If the above occurs before or at the same time as the case below (and the scheduler chooses to the above case), the goroutine above the select block would be leaked as it is blocked by the send to the done channel.

		go func() {
			done <- b.cmd.Wait()
		}()

		select {
		case err := <-done:
			if err != nil {
				log.G(ctx).WithError(err).Errorf("error while waiting for binary cmd to finish")
			}