chore(kitchenowl): update image docker.io/tombursch/kitchenowl-web digest to c640f2f (#43531)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| docker.io/tombursch/kitchenowl-web | digest | `70c4af1` -> `c640f2f` |

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charts/stable/kitchenowl/Chart.yaml

@@ -40,5 +40,5 @@ sources:
   - https://hub.docker.com/r/tombursch/kitchenowl-web
   - https://tombursch.github.io/kitchenowl
 type: application
-version: 12.13.5
+version: 12.13.6
 

charts/stable/kitchenowl/values.yaml

@@ -1,7 +1,7 @@
 image:
   repository: docker.io/tombursch/kitchenowl-web
   pullPolicy: IfNotPresent
-  tag: latest@sha256:70c4af1d2167fa29c3809e666a8307c279f31f869ec264e7866bea8979c808d0
+  tag: latest@sha256:c640f2f38fbd24fff630d643969300cfd9a64fd81e53681fef6a8186e15918da
 backendImage:
   repository: docker.io/tombursch/kitchenowl
   pullPolicy: IfNotPresent