Added -dev composer dependencies

Author: andrewbess

composer.json

@@ -61,7 +61,7 @@
         "laminas/laminas-view": "~2.12.0",
         "league/flysystem": "^2.0",
         "league/flysystem-aws-s3-v3": "^2.0",
-        "magento/composer": "1.7.0",
+        "magento/composer": "1.8.x-dev as 1.8.0",
         "magento/magento-composer-installer": ">=0.1.11",
         "magento/zendframework1": "~1.14.2",
         "monolog/monolog": "^2.3",