Helm chart does not generate volumeSnapshot configuration

I noticed that the Helm values mention that the backup method can be either barmanObjectStore (default) or volumeSnapshot:

Backup method, can be `barmanObjectStore` (default) or `volumeSnapshot`
https://github.com/cloudnative-pg/charts/blob/cluster-v0.6.1/charts/cluster/values.yaml#L489

However, I couldn't find any references to volumeSnapshot in the chart templates. I expect the following configuration to generate the corresponding resources:

```
- name: vs-daily
schedule: "0 0 2 * * *"
backupOwnerReference: self
method: volumeSnapshot
```

Instead: no volumeSnapshot section defined on the target cluster

Which makes sense, since there doesn't seem to be any volumeSnapshot configuration generated by the chart.

Am I missing some additional required configuration, or is volumeSnapshot support currently incomplete/outdated in the Helm chart documentation?

Thanks.