chore(helm): update image ghcr.io/open-webui/open-webui digest to a73dcd1 (#35732)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| ghcr.io/open-webui/open-webui | digest | `28a8242` -> `a73dcd1` |

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

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Automerge - At any time (no schedule defined).

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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

@@ -38,5 +38,5 @@ sources:
   - https://github.com/truecharts/charts/tree/master/charts/stable/ollama
   - https://hub.docker.com/r/ollama/ollama
 type: application
-version: 7.15.2
+version: 7.15.3
 

charts/stable/ollama/values.yaml

@@ -9,7 +9,7 @@ rocmImage:
 uiImage:
   repository: ghcr.io/open-webui/open-webui
   pullPolicy: IfNotPresent
-  tag: latest@sha256:28a8242c1bb7518b81723ebad12bfb3d464e0a6199a838c6cd71548e077013b0
+  tag: latest@sha256:a73dcd1a6d95b6f295cd991588c5df013a0c26a05b1d555aaa94b1d1cf560b39
 
 securityContext:
   container: