Fatal error: Uncaught Error: Cannot instantiate interface Amasty\PageSpeedOptimizer\Model\Output\OutputChainInterface in /var/www/headcovers/builds/feb192020_101832/vendor/magento/framework/ObjectManager/Factory/AbstractFactory.php:116 Stack trace: #0 /var/www/headcovers/builds/feb192020_101832/vendor/magento/framework/ObjectManager/Factory/Compiled.php(108): Magento\Framework\ObjectManager\Factory\AbstractFactory->createObject('Amasty\\PageSpee...', Array) #1 /var/www/headcovers/builds/feb192020_101832/vendor/magento/framework/ObjectManager/Factory/Compiled.php(150): Magento\Framework\ObjectManager\Factory\Compiled->create('Amasty\\PageSpee...') #2 /var/www/headcovers/builds/feb192020_101832/vendor/magento/framework/ObjectManager/Factory/Compiled.php(79): Magento\Framework\ObjectManager\Factory\Compiled->get('Amasty\\PageSpee...') #3 /var/www/headcovers/builds/feb192020_101832/vendor/magento/framework/ObjectManager/ObjectManager.php(70): Magento\Framework\ObjectManager\Factory\Compiled->create('Amasty\\PageSpee...') #4 / in /var/www/headcovers/builds/feb192020_101832/vendor/magento/framework/ObjectManager/Factory/AbstractFactory.php on line 116