Update composer.json

Author: driesvints

composer.json

@@ -12,7 +12,7 @@
     "require": {
         "php": "^7.2.9",
         "ext-zip": "*",
-        "guzzlehttp/guzzle": "^6.0",
+        "guzzlehttp/guzzle": "^6.0|^7.0",
         "symfony/console": "^4.0|^5.0",
         "symfony/filesystem": "^4.0|^5.0",
         "symfony/process": "^4.2|^5.0"