feat(website) add longhorn snapshot-delete/cleanup task info (#32031)

**Description**

add longhorn snapshot-delete/cleanup task info

⚒️ Fixes  # <!--(issue)-->

**⚙️ Type of change**

- [x] ⚙️ Feature/App addition
- [ ] 🪛 Bugfix
- [ ] ⚠️ Breaking change (fix or feature that would cause existing
functionality to not work as expected)
- [ ] 🔃 Refactor of current code

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**✔️ Checklist:**

- [x] ⚖️ My code follows the style guidelines of this project
- [x] 👀 I have performed a self-review of my own code
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areas
- [ ] 📄 I have made corresponding changes to the documentation
- [ ] ⚠️ My changes generate no new warnings
- [ ] 🧪 I have added tests to this description that prove my fix is
effective or that my feature works
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- [ ] I made sure the title starts with `feat(chart-name):`,
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**➕ App addition**

If this PR is an app addition please make sure you have done the
following.

- [ ] 🖼️ I have added an icon in the Chart's root directory called
`icon.png`

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website/src/content/docs/clustertool/csi/longhorn.md

@@ -27,7 +27,6 @@ Longhorn wont free/trim the space gained by the deletion of the snapshots and wi
 This can be prevented by adding the following `ReccuringTask` to Longhorn:
 
 ```yaml
-
 apiVersion: longhorn.io/v1beta2
 kind: RecurringJob
 metadata:
@@ -41,11 +40,54 @@ spec:
   name: trim
   retain: 0
   task: filesystem-trim
-
 ```
-This runs a filesystem trim on midnight cet. To free the "used" space.
+This runs a filesystem trim at midnight UTC. To free the "used" space.
+
+In addition to trim, it is possible to delete and cleanup all snapshots by adding tasks for snapshot-delete and snapshot-cleanup.
+
+:::caution
+
+This tasks should only be used with caution, as they will delete manually created snapshots too.
+
+:::
+
+
+```yaml
+apiVersion: longhorn.io/v1beta2
+kind: RecurringJob
+metadata:
+  name: delete
+  namespace: longhorn-system
+spec:
+  concurrency: 1
+  cron: 00 22 * * *
+  groups:
+  - default
+  name: delete
+  retain: 0
+  task: snapshot-delete
+```
+This runs a snapshot delete task at 22:00 UTC.
+
+```yaml
+apiVersion: longhorn.io/v1beta2
+kind: RecurringJob
+metadata:
+  name: cleanup
+  namespace: longhorn-system
+spec:
+  concurrency: 1
+  cron: 30 22 * * *
+  groups:
+  - default
+  name: cleanup
+  retain: 0
+  task: snapshot-cleanup
+```
+This runs a snapshot cleanup task at 22:30 UTC.
 
 ## Other references
 
-<https://longhorn.io/docs/1.7.1/deploy/install/install-with-helm/>
-<https://volsync.readthedocs.io/en/latest/installation/index.html>
+<https://longhorn.io/docs/1.8.0/deploy/install/install-with-helm> \
+<https://volsync.readthedocs.io/en/latest/installation/index.html> \
+<https://longhorn.io/docs/1.8.0/snapshots-and-backups/scheduling-backups-and-snapshots/#using-the-manifest>