process: Always kick job scheduler when a worker finishes

process: Always kick job scheduler when a worker finishes

If we happen to have a very long running job, it is not desired that
all other jobs remain stuck waiting this job to complete. This can
happen if we first start all jobs, causing the scheduler to wait
indefinitely for a "kick", then the last job takes forever to finish.

To fix this, every time a job finishes, it is better to reschedule the
job poller in case new job has become schedulable.

Signed-off-by: Timo Kokkonen <timo.t.kokkonen@iki.fi>