executor/save_boot_artifact: add support for a user-provided log function
This enables users to redirect the output of save_boot_artifact to any stream they want. This will be useful to redirect the output to the job console.
Due to an influx of spam, we have had to impose restrictions on new accounts. Please see this wiki page for instructions on how to get full permissions. Sorry for the inconvenience.
This enables users to redirect the output of save_boot_artifact to any stream they want. This will be useful to redirect the output to the job console.