ENGCOM-6282: M2C-21765 Output N/A if attribute has no value in Compare List #25585

 - Merge Pull Request #25585 from ptylek/magento2:fix-issue_compare_page-M2C-21765
 - Merged commits:
   1. 9ea1d3f
   2. 1f010f1

Author: magento-engcom-team

app/code/Magento/Catalog/view/frontend/templates/product/compare/list.phtml

@@ -130,6 +130,8 @@
                                             default :?>
                                                 <?php if (is_string($block->getProductAttributeValue($item, $attribute))) :?>
                                                     <?= /* @noEscape */ $helper->productAttribute($item, $block->getProductAttributeValue($item, $attribute), $attribute->getAttributeCode()) ?>
+                                                <?php else : ?>
+                                                    <?=  $block->escapeHtml($helper->productAttribute($item, $block->getProductAttributeValue($item, $attribute), $attribute->getAttributeCode())) ?>
                                                 <?php endif; ?>
                                                 <?php break;
                                         } ?>