Feedback on /install/container/kubernetes/kubernetes.rst

### Documentation feedback

- Page title: CrateDB and Kubernetes
- Page URL: https://cratedb.com/docs/guide/install/container/kubernetes/kubernetes.html
- Source: https://github.com/crate/cratedb-guide/blob/main/docs/install/container/kubernetes/kubernetes.rst

---

The page includes a snippet about `volumeClaimTemplates`, but @WalBeh mentioned at https://github.com/crate/cratedb-guide/pull/395#discussion_r2421597022 that a `PersistentVolumeClaim` would be expected.

```yaml
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
annotations:
pv.kubernetes.io/bind-completed: "yes"
pv.kubernetes.io/bound-by-controller: "yes"
finalizers:
- kubernetes.io/pvc-protection
labels:
app.kubernetes.io/component: cratedb
app.kubernetes.io/name: xxx
cloud.crate.io/node-name: hot
name: data0-crate-data-hot-xxx-0
namespace: xx
```

Maybe the original configuration snippet is outdated?