cant delete/update a workspace that does not have a backup configuration

[vrabbi]

when creating a workspace the backup stanza is optional but if you dont configure a backup any future terraform apply or destroy commands fail with the following error:

Error:  &{Code:BackupNotConfigured Details:<nil> Message:Backup not configured Ref:c8a99b97712fbd2471834ff35719be9a781604879c41a38db1561d3e5c77f43e}