iotests/qsd-jobs: Filter events in the first test

iotests/qsd-jobs: Filter events in the first test

The job may or may not be ready before the 'quit' is issued.  Whether it
is is irrelevant; for the purpose of the test, it only needs to still be
there.  Filter the job status change and READY events from the output so
it becomes reliable.

Reported-by: Peter Maydell <peter.maydell@linaro.org>
Suggested-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20210401132839.139939-1-mreitz@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>