Depends on D4028

Since we'll need the created field in multiple places in the database (backup item, backup id in holder in the blob item) it's good that it's the same value

Run the blob service
Run the backup service
Use grpc-playground to make a call creating a new backup

Check in the database that the new backup item and the holder for the reverse index item (in the blob) have the same part derived from the created field - you can also log this out in the code.