chore(helm): update image ghcr.io/cloudnative-pg/postgresql 16.6 → 16.8 (#32724)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| ghcr.io/cloudnative-pg/postgresql | minor |  ->  |

Add the preset `:preserveSemverRanges` to your config if you don't want
to pin your dependencies.

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Signed-off-by: Alfred Göppel <43101280+alfi0812@users.noreply.github.com>
Co-authored-by: Alfred Göppel <43101280+alfi0812@users.noreply.github.com>

charts/library/common/Chart.yaml

@@ -48,4 +48,4 @@ sources:
   - https://hub.docker.com/_/
   - https://hub.docker.com/r/mikefarah/yq
 type: library
-version: 26.4.1
+version: 26.4.2

charts/library/common/values.yaml

@@ -549,7 +549,7 @@ postgres15Image:
 
 postgres16Image:
   repository: ghcr.io/cloudnative-pg/postgresql
-  tag: "16.6"
+  tag: "16.8"
   pullPolicy: IfNotPresent
 
 postgresPostgis15Image: