Ticket 49072 - validate memberof fixup task args
Bug Description: If an invalid base dn, or invalid filter was provided
in the task there was no way to tell thathte task
actually failed.
Fix Description: Log an error, and properly update the task status/exit
code when an error occurs.
Added CI test (also fixed some issues in the dynamic
plugins test suite).
https://fedorahosted.org/389/ticket/49072
Reviewed by: nhosoi(Thanks!)
(cherry picked from commit a79ae70df6b20cd288fca511f784c414e8c52df4)