ci_run_n_monitor: update job when it goes through enable_job()

ci_run_n_monitor: track job when it goes through enable_job()

`enable_job()` modifies the job, so we need to make sure we get the
updated job back out of it.

ci_run_n_monitor: track new job when retrying a job

When retrying a job, we are creating a new job, so we need to keep track
of this new job now.

ci_run_n_monitor: refresh job state when starting it

Avoids job staying in 'manual' state and making the script think there's
nothing left running.