public function addEditButton(array &$field, $field_name) {
    $field['#buttons']['edit'] = [
      '#type' => 'link',
      '#title' => $this->t('Edit'),
      '#url' => Url::fromRoute('acm_customer.view_page', [
        'page' => $this->getPageId(),
        'action' => 'edit',
        'id' => $field_name,
      ]),
      '#attributes' => [
        'class' => [
          'form-item__edit-button',
        ],
      ],
    ];
  }