chore(deps): update postgres:15.13 docker digest to 3156e13 (rnaveiras#379)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| postgres | digest | `e652bef` -> `3156e13` |

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Author: rnaveiras

compose.yaml

@@ -49,7 +49,7 @@ services:
     # renovate: datasource=docker depName=postgres versioning=docker
     # renovate: allowedVersions=15.x
     <<: *postgres
-    image: postgres:15.13@sha256:e652befe0cc7d0e312828d71522aed8ed3762d6b71b6a5a823821ff06c186a20
+    image: postgres:15.13@sha256:3156e13d976072c9083fe4c56455b8515dcf6fee23fd770e6ba4a3c6b8837337
     volumes:
       - postgres_data_15:/var/lib/postgresql/data
       - ./docker/postgresql.conf:/etc/postgresql/postgresql.conf