Hi team, I'm actually facing a problem.. I have a postgres instance running on a seperate container, and I want to connect supertokens container to the  postgres container. I think I am facing issue at POSTGRESQL_HOST.. This is my docker command:  
sudo docker run -p 3567:3567 -e POSTGRESQL_USER="postgres" -e POSTGRESQL_PASSWORD="postgres" -e POSTGRESQL_HOST="host" -e POSTGRESQL_PORT="5432" -e POSTGRESQL_DATABASE_NAME="supertokens" -d registry.supertokens.io/supertokens/supertokens-postgresql
This is my postgres docker-compose.yml:
version: '3'
services:
  db:
    image: postgres:latest
    environment:
      POSTGRES_USER: user
      POSTGRES_PASSWORD: pass
      POSTGRES_DB: supertokens
    ports:
      - 5432:5432
    networks:
      - db
    restart: unless-stopped
  supertokens:
    image: registry.supertokens.io/supertokens/supertokens-postgresql
    depends_on:
      - db
    ports:
      - 3567:3567
    environment:
      POSTGRESQL_CONNECTION_URI : postgresql://user:pass@db/supertokens
    networks:
      - db
    restart: unless-stopped
networks:
  db:
    driver: bridge