Fatal error: Uncaught Error: Interface 'Magento\ConfigurableProduct\Api\LinkManagementInterface' not found in /home/esecureh/public_html/magdemo/vendor/magento/module-configurable-product/Model/LinkManagement.php:18 Stack trace: #0 {main} thrown in /home/esecureh/public_html/magdemo/vendor/magento/module-configurable-product/Model/LinkManagement.php on line 18