Fix control lock/update issue. Fix flaky system test. Add debugging stuff.

@michael.prilop, @lutz.maicher

This MR fixes a bug in the dossier control where the update request is fired before the lock request succeeded. This normally doesn't happen but was a problem in system tests where the control was triggered really fast.

This also fixes a flaky system test by adding some more time to wait.

And I also added some debugging stuff which I used and maybe could help in the future.