feat: switch to postgres docker images with pgvector support (v4.0) (#10658)

Starting v4.0, pgvector support is mandatory. This PR adds pgvector
support for new docker installations.

- Switch to postgres images with pgvector support
- Change the default postgres version from `12` to `16`

.devcontainer/docker-compose.yml

@@ -40,7 +40,7 @@ services:
     network_mode: service:db
 
   db:
-    image: postgres:latest
+    image: pgvector/pgvector:pg16
     restart: unless-stopped
     volumes:
       - postgres-data:/var/lib/postgresql/data