tests: Wait for automember rebuild --no-wait tasks to finish
The behavior of automember changed with the design
https://www.port389.org/docs/389ds/design/automember-postop-modify-design.html
such that members are "cleaned up" first then re-added. This has
the effect of removing members that no longer apply to a rule.
This was breaking the automember rebuild tests because sometimes
the tests were faster than 389-ds causing memberships to be missed.
This does a client-side wait for the task to finish up so still
exercises the rebuild code.
https://pagure.io/freeipa/issue/7972
Signed-off-by: Rob Crittenden <rcritten@redhat.com>
Reviewed-By: Florence Blanc-Renaud <frenaud@redhat.com>
Reviewed-By: Christian Heimes <cheimes@redhat.com>