chore(grafana-image-renderer): update image docker.io/grafana/grafana-image-renderer digest to ff3209c (#45465)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| docker.io/grafana/grafana-image-renderer | digest | `36e89ef` →
`ff3209c` |

---

> [!WARNING]
> Some dependencies could not be looked up. Check the [Dependency
Dashboard](../issues/18710) for more information.

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/grafana-image-renderer/Chart.yaml

@@ -41,5 +41,5 @@ sources:
   - https://github.com/trueforge-org/truecharts/tree/master/charts/stable/grafana-image-renderer
   - https://hub.docker.com/r/grafana/grafana-image-renderer
 type: application
-version: 8.15.0
+version: 8.15.1
 

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

@@ -2,7 +2,7 @@
 image:
   pullPolicy: IfNotPresent
   repository: docker.io/grafana/grafana-image-renderer
-  tag: latest@sha256:36e89efeb2a384e39ac06a3aaa5e5f44474dbd425c1353a150005fca31e4dcd7
+  tag: latest@sha256:ff3209c57a67faa164a9e5c91510b7c7c931d6edab3a457852737031bb3545a6
 persistence: {}
 
 securityContext: