chore(helm): update image ghcr.io/techno-tim/littlelink-server digest to d73ac74 (#28495)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| ghcr.io/techno-tim/littlelink-server | digest | `42917c3` -> `d73ac74`
|

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

---

### 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/littlelink/Chart.yaml

@@ -33,4 +33,4 @@ sources:
   - https://github.com/techno-tim/littlelink-server
   - https://github.com/truecharts/charts/tree/master/charts/stable/littlelink
 type: application
-version: 15.2.1
+version: 15.2.2

charts/stable/littlelink/values.yaml

@@ -1,7 +1,7 @@
 image:
   repository: ghcr.io/techno-tim/littlelink-server
   pullPolicy: IfNotPresent
-  tag: latest@sha256:42917c3ef616a679e637faf78b69231f815d57b6ab1fada06f2fb09f67c504e1
+  tag: latest@sha256:d73ac74bb3317d13b76c5f62a45ccc0a1eaa6c9ca8819ec417762fecac9052a5
 service:
   main:
     ports: