build(deps): bump postgres in /Containers/postgresql

Bumps postgres from 16.8-alpine to 16.9-alpine.

---
updated-dependencies:
- dependency-name: postgres
  dependency-version: 16.9-alpine
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

Containers/postgresql/Dockerfile

@@ -1,6 +1,6 @@
 # syntax=docker/dockerfile:latest
 # From https://github.com/docker-library/postgres/blob/master/16/alpine3.21/Dockerfile
-FROM postgres:16.8-alpine
+FROM postgres:16.9-alpine
 
 COPY --chmod=775 start.sh /start.sh
 COPY --chmod=775 healthcheck.sh /healthcheck.sh