Ignore multiselect attributes from plugin

[Jakhotiya]

Product listing page and search page shows empty area in product listing area when filter for a multiselect swatch attribute is applied. \Smile\ElasticsuiteSwatches\Model\Plugin\ProductImage class has getFilterArray method. This method can return array of format [ "color" => [ "blue","red" ] ] This further causes array to string conversion in vendor/magento/module-swatches/Helper/Data.php on line 199 For reproducing the issue create color as a swatch attribute, filterable on product listing page. You will see Notice: Array to string conversion in vendor/magento/module-swatches/Helper/Data.php on line 199 in system.log