Test 517: avoid command chaining

Long description:

Command chaining seems to introduce concurrency problems with the test
suite or the ipc that are not being tested in this case.

To apply this patch, use:
curl http://cr.i3wm.org/patch/478/raw.patch | git am

@@ -68,7 +68,8 @@ is(@{$event->{current}->{nodes}}, 1, 'focus event gave the right number of windo

 # reset and try again

 $focus = AnyEvent->condvar;

-cmd 'workspace ws-left; move right';

+cmd 'workspace ws-left';

+cmd 'move right';

 $event = $focus->recv;

 ok($event, 'moving from workspace with one window triggered focus ipc event');

 is($event->{current}->{name}, 'ws-right', 'focus event gave the right workspace');