chore(helm): update image ghcr.io/linuxserver/grocy digest to c7c842c (#28412)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
|
[ghcr.io/linuxserver/grocy](https://redirect.github.com/linuxserver/docker-grocy/packages)
([source](https://redirect.github.com/linuxserver/docker-grocy)) |
digest | `586618e` -> `c7c842c` |

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

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charts/stable/grocy/Chart.yaml

@@ -33,4 +33,4 @@ sources:
   - https://github.com/grocy/grocy
   - https://github.com/truecharts/charts/tree/master/charts/stable/grocy
 type: application
-version: 20.2.1
+version: 20.2.2

charts/stable/grocy/values.yaml

@@ -1,6 +1,6 @@
 image:
   repository: ghcr.io/linuxserver/grocy
-  tag: 4.2.0@sha256:586618e9049afb408c05f24804e4399a1db296c05cec65cabb539356c9f3ae36
+  tag: 4.2.0@sha256:c7c842c5b77b48256e8bb6434cbad7f972ec2b8a304410dee0604a359482577f
   pullPolicy: IfNotPresent
 service:
   main: