chore(common): update image ghcr.io/cloudnative-pg/postgresql digest to 50d26bf (#45966)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| ghcr.io/cloudnative-pg/postgresql | digest | `e2c52cb` → `50d26bf` |

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charts/library/common/Chart.yaml

@@ -50,4 +50,5 @@ sources:
   - https://github.com/trueforge-org/truecharts/tree/master/charts/library/common
   - https://hub.docker.com/_/
 type: library
-version: 28.33.3
+version: 28.33.4
+

charts/library/common/values.yaml

@@ -643,7 +643,7 @@ mongodbClientImage:
 
 postgres15Image:
   repository: ghcr.io/cloudnative-pg/postgresql
-  tag: "15.17@sha256:e2c52cb374b218f4ea175f331530316d5c0000e56a7089114f54a222db879ff8"
+  tag: "15.17@sha256:50d26bf9622ec259c9a2d2906a66c3ba9f3b106c91b4a8120d1e20c6a43b32a7"
   pullPolicy: IfNotPresent
 
 postgres16Image: