chore(deps): update postgres docker tag to v15.7 (#764)

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This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| postgres | minor | `15.4` -> `15.7` |

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Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>
Co-authored-by: Ole Jørgen Skogstad <skogstad@softis.net>

Author: renovate[bot]

docker-compose-no-webapi.yml

@@ -2,7 +2,7 @@ version: '3.9'
 
 services:
   dialogporten-postgres:
-    image: postgres:15.4
+    image: postgres:15.6
     restart: always
     command: postgres -c wal_level=logical
     environment: