Update Helm release postgres-cluster to v6

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [rook-ceph-cluster](https://github.com/rook/rook) | minor | `v1.17.8` -> `v1.18.0` |

---

### Release Notes

<details>
<summary>rook/rook (rook-ceph-cluster)</summary>

### [`v1.18.0`](https://github.com/rook/rook/releases/tag/v1.18.0)

[Compare Source](https://github.com/rook/rook/compare/v1.17.8...v1.18.0)

#### Upgrade Guide

To upgrade from previous versions of Rook, see the [Rook upgrade guide](https://rook.github.io/docs/rook/v1.18/Upgrade/rook-upgrade/).

#### Breaking Changes

- Kubernetes v1.29 is now the minimum version supported by Rook through the soon-to-be K8s release v1.34.
- Helm versions 3.13 and newer are supported. Previously, only the latest version of helm was tested and the docs stated only version 3.x of helm as a prerequisite. Now rook supports the six most recent minor versions of helm along with their their patch updates.
- Rook now validates node topology during CephCluster creation to prevent misconfigured CRUSH hierarchies for OSDs. If child labels like `topology.rook.io/rack` are duplicated across zones, cluster creation will fail. The check applies only to new clusters without OSDs. Clusters with existing OSDs will only log a warning and continue. If the checks are invalid in your topology, they can be suppressed by setting `ROOK_SKIP_OSD_TOPOLOGY_CHECK=true` in the `rook-ceph-operator-config` configmap.

#### Features

- The Ceph CSI operator is now the default and recommended component for configuring CSI drivers for RBD, CephFS, and NFS volumes. The CSI operator has been factored out of Rook to run independently to manage the Ceph-CSI driver. 
  - During the upgrade and throughout the v1.18.x releases, Rook will automatically convert any Rook CSI settings to the new CSI operator CRs. This transition is expected to be completely transparent. In the future v1.19 release, Rook will relinquish direct control of these settings so advanced users can have more flexibility when configuring the CSI drivers. At that time, we will have a guide on configuring these new Ceph CSI operator CRs directly.
  - During install, as mentioned in the [Quickstart Guide](https://rook.io/docs/rook/latest-release/Getting-Started/quickstart/#deploy-the-rook-operator), there is a new manifest to be created: csi-operator.yaml
  - If installing with the helm chart, the Ceph CSI operator will automatically be installed by default with the new helm setting `csi.rookUseCsiOperator` in the rook-ceph chart.
  - If a blocking issue is found, the previous CSI driver can be re-enabled by setting `ROOK_USE_CSI_OPERATOR: false` in operator.yaml or by applying the helm setting `csi.rookUseCsiOperator: false`.
- [Ceph CSI v3.15](https://github.com/ceph/ceph-csi/releases/tag/v3.15.0) has a range of features and improvements for the RBD, CephFS, and NFS drivers. This release is supported both by the Ceph CSI operator and Rook's direct mode of configuration. Starting in the next release (at the end of the year), the Ceph CSI operator will be required to configure the CSI driver.
- [CephX key rotation](https://rook.io/docs/rook/v1.18/Storage-Configuration/Advanced/cephx-key-rotation/?h=cephx) is now available as an **experimental** feature for the CephX authentication keys used by Ceph daemons and clients. Users will begin to see new cephx status items on some Rook resources in newly-deployed Rook clusters. Users can also find `spec.security.cephx` settings that allow initiating CephX key rotation for various Ceph components. Full documentation for key rotation can be found [here](https://rook.io/docs/rook/v1.18/Storage-Configuration/Advanced/cephx-key-rotation/?h=cephx).
  - Ceph version v19.2.3+ is required for key rotation.
  - The Ceph admin and mon keys cannot yet be rotated. Implementation is still in progress while in experimental mode.
- Add support for specifying the clusterID in the [CephBlockPoolRadosNamespace](https://rook.io/docs/rook/v1.18/CRDs/Block-Storage/ceph-block-pool-rados-namespace-crd/#creating-a-storage-class) and the [CephFilesystemSubVolumeGroup](https://rook.io/docs/rook/v1.18/CRDs/Shared-Filesystem/ceph-fs-subvolumegroup-crd/#create-a-storage-class-for-the-subvolume-group) CR.
- When a mon is being [failed over](https://rook.io/docs/rook/latest-release/Storage-Configuration/Advanced/ceph-mon-health/#failing-over-a-monitor), if the assigned node no longer exists, the mon is failed over immediately instead of waiting for a
  20 minute timeout.
- Support for Ceph Tentacle v20 will be available as soon as it is released.

</details>

---

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---

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clusters/cl01tl/storage/rook-ceph/Chart.yaml

@@ -19,7 +19,7 @@ dependencies:
     version: v1.18.0
     repository: https://charts.rook.io/release
   - name: rook-ceph-cluster
-    version: v1.17.8
+    version: v1.18.0
     repository: https://charts.rook.io/release
   - name: cloudflared
     alias: cloudflared-rgw