chore(flux): update image kube-prometheus-stack 77.7.0 → 77.8.0 (clustertool) (#39616)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
|
[kube-prometheus-stack](https://redirect.github.com/prometheus-operator/kube-prometheus)
([source](https://redirect.github.com/prometheus-community/helm-charts))
| minor | `77.7.0` -> `77.8.0` |

---

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

---

### Release Notes

<details>
<summary>prometheus-community/helm-charts
(kube-prometheus-stack)</summary>

###
[`v77.8.0`](https://redirect.github.com/prometheus-community/helm-charts/releases/tag/kube-prometheus-stack-77.8.0)

[Compare
Source](https://redirect.github.com/prometheus-community/helm-charts/compare/kube-prometheus-stack-77.7.0...kube-prometheus-stack-77.8.0)

kube-prometheus-stack collects Kubernetes manifests, Grafana dashboards,
and Prometheus rules combined with documentation and scripts to provide
easy to operate end-to-end Kubernetes cluster monitoring with Prometheus
using the Prometheus Operator.

#### What's Changed

- \[kube-prometheus-stack] Update <https://github.com/etcd-io/etcd>
digest to
[`ad9d690`](https://redirect.github.com/prometheus-community/helm-charts/commit/ad9d690)
by [@&#8203;renovate](https://redirect.github.com/renovate)\[bot] in
[#&#8203;6138](https://redirect.github.com/prometheus-community/helm-charts/pull/6138)

**Full Changelog**:
<https://github.com/prometheus-community/helm-charts/compare/kube-prometheus-stack-77.7.0...kube-prometheus-stack-77.8.0>

</details>

---

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clustertool/embed/generic/kubernetes/system/kube-prometheus-stack/app/helm-release.yaml

@@ -10,7 +10,7 @@ spec:
   chart:
     spec:
       chart: kube-prometheus-stack
-      version: 77.7.0
+      version: 77.8.0
       sourceRef:
         kind: HelmRepository
         name: prometheus-community