chore(helm): update image docker.io/grafana/grafana-image-renderer digest to 6f70ad1 (#39380)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| docker.io/grafana/grafana-image-renderer | digest | `80adf96` ->
`6f70ad1` |

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charts/stable/grafana-image-renderer/Chart.yaml

@@ -36,5 +36,5 @@ sources:
   - https://github.com/truecharts/charts/tree/master/charts/stable/grafana-image-renderer
   - https://hub.docker.com/r/grafana/grafana-image-renderer
 type: application
-version: 8.4.1
+version: 8.4.2
 

charts/stable/grafana-image-renderer/values.yaml

@@ -1,7 +1,7 @@
 image:
   pullPolicy: IfNotPresent
   repository: docker.io/grafana/grafana-image-renderer
-  tag: latest@sha256:80adf96df3a18372db5697a6706b86792ed424d3bab9d6bfd0b91820c2324969
+  tag: latest@sha256:6f70ad1547e5015affc3cdb0254d21359cfb7556419030b9fbf7175eb6f7bb65
 persistence: {}
 
 securityContext: