chore(deps): update container image bitnami/alertmanager to 0.27.0@b81c92c by renovate (#21472)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [bitnami/alertmanager](https://togithub.com/bitnami/containers)
([source](https://togithub.com/bitnami/containers/tree/HEAD/bitnami/alertmanager))
| digest | `4698b7d` -> `b81c92c` |

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This PR has been generated by [Renovate
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<!--renovate-debug:eyJjcmVhdGVkSW5WZXIiOiIzNy4zNDEuMCIsInVwZGF0ZWRJblZlciI6IjM3LjM0MS4wIiwidGFyZ2V0QnJhbmNoIjoibWFzdGVyIiwibGFiZWxzIjpbImF1dG9tZXJnZSIsInVwZGF0ZS9kb2NrZXIvZ2VuZXJhbC9ub24tbWFqb3IiXX0=-->

charts/premium/prometheus/Chart.yaml

@@ -29,7 +29,7 @@ home: https://truecharts.org/charts/premium/prometheus
 icon: https://truecharts.org/img/hotlink-ok/chart-icons/prometheus.webp
 keywords:
   - metrics
-kubeVersion: ">=1.24.0-0"
+kubeVersion: '>=1.24.0-0'
 maintainers:
   - name: TrueCharts
     email: info@truecharts.org
@@ -40,7 +40,7 @@ sources:
   - https://github.com/prometheus-operator/kube-prometheus
   - https://github.com/truecharts/charts/tree/master/charts/premium/prometheus
   - https://hub.docker.com/r/bitnami/prometheus
-  - https://quay.io/thanos/thanos
   - https://hub.docker.com/r/bitnami/alertmanager
+  - https://quay.io/thanos/thanos
 type: application
-version: 18.0.5
+version: 18.0.6

charts/premium/prometheus/values.yaml

@@ -6,7 +6,7 @@ thanosImage:
   tag: v0.34.1@sha256:567346c3f6ff2927c2c6c0daad977b2213f62d45eca54d48afd19e6deb902181
 alertmanagerImage:
   repository: bitnami/alertmanager
-  tag: 0.27.0@sha256:4698b7d1924a9bf36dc16be725e6646af3e6068b0ffc2d405c160109c578ef91
+  tag: 0.27.0@sha256:b81c92c4ce171c065049a7d600bf4e5813eb8ae64d81d96d88462eed9f03d873
 global:
   labels: {}
 workload: