changes composer package

Author: shopifychamp

composer.json

@@ -16,7 +16,7 @@
         "rdx/graphql-query" : "^1.1"
     },
     "require-dev":{
-        "guzzlehttp/guzzle": "^7.2.0",
+        "guzzlehttp/guzzle": "^6.3.1|^7.0.1",
         "phpunit/phpunit": "^6.5"
     },
     "autoload": {