Function sleep

spanner/system-test/spanner.test.js:1702–1704

(timeMillis)

    // delete_backup
    it('should delete a backup', async () => {
      function sleep(timeMillis) {
        return new Promise(resolve => setTimeout(resolve, timeMillis));
      }

      // Wait for database to finish optimizing - cannot delete a backup if a database restored from it
      const instance = spanner.instance(INSTANCE_ID);