chore(helm): update image docker.io/bitnami/prometheus digest to 8f11ee3 (#28288)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
|
[docker.io/bitnami/prometheus](https://redirect.github.com/bitnami/containers)
([source](https://redirect.github.com/bitnami/containers/tree/HEAD/bitnami/prometheus))
| digest | `5f7de03` -> `8f11ee3` |

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to pin your dependencies.

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charts/premium/prometheus/Chart.yaml

@@ -42,4 +42,4 @@ sources:
   - https://hub.docker.com/r/bitnami/prometheus
   - https://quay.io/thanos/thanos
 type: application
-version: 19.25.1
+version: 19.25.2

charts/premium/prometheus/values.yaml

@@ -1,6 +1,6 @@
 image:
   repository: docker.io/bitnami/prometheus
-  tag: 2.55.0@sha256:5f7de03c79d4192e09b3674d053c2d25c354c32c485d0895d75e7950745df70f
+  tag: 2.55.0@sha256:8f11ee33d862ffd0282e289ac72f1e2006741369e287534b1a72429ee03a8b72
 thanosImage:
   repository: quay.io/thanos/thanos
   tag: v0.36.1@sha256:e542959e1b36d5046083d1b64a7049c356b68a44a173c58b3ae7c0c9ada932d5