Scenario: remove the `addCleanup_with_wait` helper method.

It was way too complex. And not used a lot.

Also remove the related 'wait_on_delete=True' keyword argument
of "create_server" method because no caller called that method
with another value than the default value. Which proved that this
kwarg was useless.

Change-Id: Ief79a6cee55ff5faf64465f6cbc84bec8253a3e1
1 file changed