chore(common): update image ghcr.io/cloudnative-pg/postgresql digest to 17087f3 (#43307)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| ghcr.io/cloudnative-pg/postgresql | digest | `6c11bf2` -> `17087f3` |

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charts/library/common/Chart.yaml

@@ -42,5 +42,5 @@ sources:
   - https://github.com/trueforge-org/truecharts/tree/master/charts/library/common
   - https://hub.docker.com/_/
 type: library
-version: 28.29.17
+version: 28.29.18
 

charts/library/common/values.yaml

@@ -644,7 +644,7 @@ mongodbClientImage:
 
 postgres15Image:
   repository: ghcr.io/cloudnative-pg/postgresql
-  tag: "15.15@sha256:6c11bf2fa89b71ff3ed0390f863228a4a0b43fcb3e4aeca9a274e6c57c2e680a"
+  tag: "15.15@sha256:17087f3b1a618647f0c3a44c5d48a699806ce268ea664c7b5909e3b5101638bc"
   pullPolicy: IfNotPresent
 
 postgres16Image: