Updated abstract classname after GraphQL changes
Updated abstract classname after GraphQL changes

Changed connection() to createConnection() to match changes abstract method name on GraphQL module.
silverstripe/silverstripe-asset-admin,open-sausages/silverstripe-asset-admin,silverstripe/silverstripe-asset-admin,open-sausages/silverstripe-assets-gallery,open-sausages/silverstripe-assets-gallery,open-sausages/silverstripe-asset-admin