Update to Guzzle 7

Author: Martin Bean

composer.json

@@ -3,8 +3,8 @@
   "description": "PHP binding for v4 of the Cloudflare Client API.",
   "type": "library",
   "require": {
-    "guzzlehttp/guzzle": "^6.2.2",
-    "php": ">=7.0.0",
+    "guzzlehttp/guzzle": "^7.0.1",
+    "php": ">=7.2.5",
     "psr/http-message": "~1.0",
     "ext-json": "*"
   },
@@ -35,4 +35,4 @@
     "sort-packages": true,
     "optimize-autoloader": true
   }
-}
+}