Delete the default namespace setting.
delete_default_namespace.RdDeletes the default namespace setting for the workspace. A fresh etag needs
to be provided in DELETE requests (as a query parameter). The etag can be
retrieved by making a GET request before the DELETE request. If the
setting is updated/deleted concurrently, DELETE fails with 409 and the
request must be retried by using the fresh etag in the 409 response.