chore(deps): update postgres docker tag to v18 (#3646)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

website/docker-compose.yml

@@ -1,7 +1,7 @@
 services:
   db:
     container_name: ark-plus-db
-    image: postgres:16-alpine
+    image: postgres:18-alpine
     restart: always
     ports:
       - 5432:5432