chore(deps): update postgres:16.9 docker digest to 918e8e7 (rnaveiras#380)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| postgres | digest | `2e7c735` -> `918e8e7` |

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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:16.9@sha256:2e7c735993bf456ee1977c40dd82e66875e25f7ee9dfe1e5118fb24887104d85
+    image: postgres:16.9@sha256:918e8e72b35b5370901965ce3da5a355c3537cb5e10c38e82c2b6f174b758334
     volumes:
       - postgres_data_16:/var/lib/postgresql/data
       - ./docker/postgresql.conf:/etc/postgresql/postgresql.conf