use GameEventStoreInPostgresql instead of InMemory

docker/parts/docker-compose-databases.yaml

@@ -20,6 +20,7 @@ services:
 
   postgresql:
     image: postgres:17.4
+    command: postgres -c 'max_connections=500'
     environment:
       POSTGRES_PASSWORD_FILE: /run/secrets/postgresql_password
       POSTGRES_USER: event-demo