Start upload containing one or many chunks.
See https://paws-r.github.io/docs/backupstorage/start_object.html for full documentation.
backupstorage_start_object(BackupJobId, ObjectName, ThrowOnDuplicate = NULL)
[required] Backup job Id for the in-progress backup
[required] Name for the object.
Throw an exception if Object name is already exist.