message: drop only if exists
diff: @@ -81,7 +81,7 @@ module.exports = class PgClient {
  let client = new Client(Object.assign({}, config, { database: 'postgres' }));
  try {
  await client.connect();
  - await client.query(`drop database ${safeDatabaseName(config.database)}`);
  + await client.query(`drop database if exists ${safeDatabaseName(config.database)}`);
  } finally {
  client.end();
  }
  