Bump to beta 7 for Guzzle 7 to reflect

Author: unicodeveloper

composer.json

@@ -15,7 +15,7 @@
     "require": {
         "php": "^7.2",
         "illuminate/support": "~6|~7|~8",
-        "cloudinary/cloudinary_php": "2.0.0-beta6",
+        "cloudinary/cloudinary_php": "2.0.0-beta7",
         "ext-json": "*"
     },
     "require-dev": {