1) utils.cleaning_error_handler() as hook in current code does not
have an exception parameter that task context manager adds.
2) It's not needed to set fail state on "NoFreeConductorWorker"
exception, this is driver specific. IPA driver can obtain a free
worker on the next heartbeat(s).
This patch also adds missing tests for error handlers functions.
Closes-Bug: #1539118
Change-Id: I9081d5b3437e9be6b68fe9c635b38f84637e93df