chore(deps): update postgres:16.8 docker digest to 301bcb6 (rnaveiras#345)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| postgres | digest | `cef2d22` -> `301bcb6` |

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Author: rnaveiras

compose.yaml

@@ -60,7 +60,7 @@ services:
     <<: *postgres
     # renovate: datasource=docker depName=postgres versioning=docker
     # renovate: allowedVersions=16.x
-    image: postgres:16.8@sha256:cef2d22004db69e3d601442ca4cac142adda0987ad7ca4f28c4e998bef690951
+    image: postgres:16.8@sha256:301bcb60b8a3ee4ab7e147932723e3abd1cef53516ce5210b39fd9fe5e3602ae
     volumes:
       - postgres_data_16:/var/lib/postgresql/data
       - ./docker/postgresql.conf:/etc/postgresql/postgresql.conf