code: public static String lookupInstanceId(String projectId, String clusterId, String zoneId)
      throws IOException {
      BigtableClusterUtilities utils;
      try {
        utils = BigtableClusterUtilities.forAllInstances(projectId);
      } catch (GeneralSecurityException e) {
        throw new RuntimeException("Could not initialize BigtableClusterUtilities", e);
      }
  
      try {
        Cluster cluster = utils.getCluster(clusterId, zoneId);
        return new BigtableClusterName(cluster.getName()).getInstanceId();
      } finally {
        try {
          utils.close();
        } catch (Exception e) {
          logger.warn("Error closing BigtableClusterUtilities: ", e);
        }
      }
    }
docs: @return The instance id associated with the given project, zone and cluster. We expect instance
  and cluster to have one-to-one relationship.
  
  @throws IllegalStateException if the cluster is not found