helpfulLinks example

// Warn the user if any updates were incompatible.     if ($incompatible_updates_exist) {
      $this->messenger()->addWarning($this->t('Some of the pending updates cannot be applied because their dependencies were not met.'));
    }

    if (empty($count)) {
      $this->messenger()->addStatus($this->t('No pending updates.'));
      unset($build);
      $build['links'] = [
        '#theme' => 'links',
        '#links' => $this->helpfulLinks($request),
      ];

      // No updates to run, so caches won't get flushed later. Clear them now.       drupal_flush_all_caches();
    }
    else {
      $build['help'] = [
        '#markup' => '<p>' . $this->t('The version of Drupal you are updating from has been automatically detected.') . '</p>',
        '#weight' => -5,
      ];
      if ($incompatible_count) {