chore(helm): update image docker.io/duplicati/duplicati digest to c6a2efd (#31540)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| docker.io/duplicati/duplicati | digest | `b463d8a` -> `c6a2efd` |

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charts/stable/duplicati/Chart.yaml

@@ -32,4 +32,4 @@ sources:
   - https://github.com/truecharts/charts/tree/master/charts/stable/duplicati
   - https://hub.docker.com/r/duplicati/duplicati
 type: application
-version: 15.5.1
+version: 15.5.2

charts/stable/duplicati/values.yaml

@@ -1,6 +1,6 @@
 image:
   repository: docker.io/duplicati/duplicati
-  tag: latest@sha256:b463d8a8f2ee2e1e79d04d7365d0e0ca07fcf20094dc9745c19a8e70d2bf1160
+  tag: latest@sha256:c6a2efddd86bdaf7c6927ea5c807986df7c0395581d061595db4884db2783ac5
   pullPolicy: IfNotPresent
 service:
   main: