fix(deploy): pass DB_PASSWORD to gateway container

Gateway datasource connects to deepdata-database with ${DB_PASSWORD};
the env var was not injected, so startup sys-param init failed with
'password authentication failed for user postgres'.

deployment/docker/deepdata/docker-compose.yml

@@ -69,6 +69,7 @@ services:
       - '8080:8080'
     environment:
       - JWT_SECRET=${JWT_SECRET:-}
+      - DB_PASSWORD=${DB_PASSWORD:?DB_PASSWORD is required. Set in .env file}
       - deepdata.jwt.enable=${DEEPDATA_JWT_ENABLE:-false}
       - LOG_ROTATION_MAX_SIZE=${LOG_ROTATION_MAX_SIZE:-100MB}
       - LOG_ROTATION_BACKUP_COUNT=${LOG_ROTATION_BACKUP_COUNT:-30}