chore(helm): update image docker.io/openaudible/openaudible digest to a4af7f2 (#33567)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| docker.io/openaudible/openaudible | digest | `f912e59` -> `a4af7f2` |

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**: 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/openaudible/Chart.yaml

@@ -32,4 +32,4 @@ sources:
   - https://github.com/truecharts/charts/tree/master/charts/stable/openaudible
   - https://hub.docker.com/r/openaudible/openaudible
 type: application
-version: 7.5.1
+version: 7.5.2

charts/stable/openaudible/values.yaml

@@ -1,7 +1,7 @@
 image:
   pullPolicy: IfNotPresent
   repository: docker.io/openaudible/openaudible
-  tag: latest@sha256:f912e5982bab568aa440f0b6121c32ff19ec0fbcb83676ca92ee90ff7e7bd7c3
+  tag: latest@sha256:a4af7f2f8a31130875b2579c5de6d964bf3573c829365079d969dd0648b76097
 persistence:
   config:
     enabled: true