Restart marge-bot on failure
Inspired by !8625 (comment 444389). In that circumstance, marge-bot crashed due to a bug or bad behavior. It would make sense to restart the service when that happens.
We could set Restart=on-failure
in the systemd service description.
Currently there is no Restart configured. It used to be Restart=always
, but it was turned off in February 2019. @bgamari or @mpickering do you happen to know why it was turned off?