chore(common): update image ghcr.io/cloudnative-pg/postgresql digest to 23d56b4 (#47741)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| ghcr.io/cloudnative-pg/postgresql | digest | `bfed15d` → `23d56b4` |

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charts/library/common/Chart.yaml

@@ -45,5 +45,5 @@ sources:
   - https://github.com/trueforge-org/truecharts/tree/master/charts/library/common
   - https://hub.docker.com/_/
 type: library
-version: 29.2.7
+version: 29.2.8
 

charts/library/common/values.yaml

@@ -643,7 +643,7 @@ mongodbClientImage:
 
 postgres15Image:
   repository: ghcr.io/cloudnative-pg/postgresql
-  tag: "15.17@sha256:bfed15dddfc3a61a7654b6748a5d8c09fec5d13c57e2350169068cb1676a666e"
+  tag: "15.17@sha256:23d56b4e6232954ba7ae9eda453a9630946f382325e3bb63af3c2c32fce9a119"
   pullPolicy: IfNotPresent
 
 postgres16Image: