[Watcher] Init:ImagePullBackOff - bad status

The benchmark pod could not start due to an error pulling the image:

Events:
  Type     Reason   Age                      From                                                 Message
  ----     ------   ----                     ----                                                 -------
  Warning  Failed   12m (x11600 over 44h)    kubelet, ip-172-16-3-152.eu-west-1.compute.internal  Error: ImagePullBackOff
  Normal   BackOff  2m26s (x11643 over 44h)  kubelet, ip-172-16-3-152.eu-west-1.compute.internal  Back-off pulling image "benchmarkai/puller:00dd240"

The watcher is interpreting it as pending initialization - we should probably update this to some error state, ask the user to --cancel the job (or issue a cancel cmd) and stop the watcher for that job.

👀 |872094df|Job is pending initialization
👀 |96f36526|Job is pending initialization
👀 |8aa5afad|Job is pending initialization
👀 |0166c689|Job is pending initialization
👀 |30ea029f|Job is pending initialization
👀 |9e5ad88c|Job is pending initialization
👀 |aaa76525|Job is pending initialization
👀 |5e0d6099|Job is pending initialization
👀 |0fdf7b9c|Job is pending initialization
👀 |608ba177|Job is pending initialization
👀 |d15f2415|Job is pending initialization
👀 |368f7697|Job is pending initialization
👀 |20f9ddd5|Job is pending initialization
👀 |63c2bffb|Job is pending initialization
👀 |1ff3627d|Job is pending initialization
....