chore(helm): update image ghcr.io/open-webui/open-webui digest to ff2413b (#28007)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| ghcr.io/open-webui/open-webui | digest | `15fe2fa` -> `ff2413b` |

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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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: 7.4.3
+version: 7.4.4

charts/stable/ollama/values.yaml

@@ -9,7 +9,7 @@ rocmImage:
 uiImage:
   repository: ghcr.io/open-webui/open-webui
   pullPolicy: IfNotPresent
-  tag: latest@sha256:15fe2fa9554a897424f6d57972fcdf4d62de459e153eb2e724cf1882fe65cdbb
+  tag: latest@sha256:ff2413bfd918b5cd198c4a7ea3a8eed9e215430298ee6076ed4c3d57c96a435d
 
 securityContext:
   container: