chore(helm): update image docker.io/bitnami/mongodb digest to af4b070 (#30810)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
|
[docker.io/bitnami/mongodb](https://redirect.github.com/bitnami/containers)
([source](https://redirect.github.com/bitnami/containers/tree/HEAD/bitnami/mongodb))
| digest | `436fc10` -> `af4b070` |

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charts/stable/mongodb/Chart.yaml

@@ -35,4 +35,4 @@ sources:
   - https://hub.docker.com/r/bitnami/mongodb
   - https://www.mongodb.com
 type: application
-version: 15.2.0
+version: 15.2.1

charts/stable/mongodb/values.yaml

@@ -1,7 +1,7 @@
 image:
   repository: docker.io/bitnami/mongodb
   pullPolicy: IfNotPresent
-  tag: 8.0.4@sha256:436fc1010ccc54518ab5115d70c2c5dcba437865259f66ee83afae4c2bb9a22d
+  tag: 8.0.4@sha256:af4b070667ddec1c70e0b8f52cd00bec1d6071b1626a88349e9b3732241a9cae
 
 includeCommon: true
 workload: