chore(helm): update image ghcr.io/open-webui/open-webui digest to caa8691 (#28507)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| ghcr.io/open-webui/open-webui | digest | `9e8ea99` -> `caa8691` |

Add the preset `:preserveSemverRanges` to your config if you don't want
to pin your dependencies.

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### Configuration

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Automerge - At any time (no schedule defined).

🚦 **Automerge**: Enabled.

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rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about this update
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charts/stable/ollama/Chart.yaml

@@ -35,4 +35,4 @@ sources:
   - https://github.com/truecharts/charts/tree/master/charts/stable/ollama
   - https://hub.docker.com/r/ollama/ollama
 type: application
-version: 7.4.11
+version: 7.4.12

charts/stable/ollama/values.yaml

@@ -9,7 +9,7 @@ rocmImage:
 uiImage:
   repository: ghcr.io/open-webui/open-webui
   pullPolicy: IfNotPresent
-  tag: latest@sha256:9e8ea9959aad4d5156d7ada8f735eb0723271d48a6d6f4815c4848e308d86543
+  tag: latest@sha256:caa86912d466525976110325f484b5b89074db189c15847b1a189fd9e1a4419a
 
 securityContext:
   container: