[FIX] README example

Author: cuaitz

README.md

@@ -72,22 +72,22 @@ Simple usage looks like:
             "capture_mode" => "automatic_async",
             "payer" => [
                 "email" => "<PAYER_EMAIL>",
-            ]
+            ],
             "transactions" => [
                 "payments" => [
-                [
-                    "amount" => "1000.00",
-                    "payment_method" => [
-                        "id" => "master",
-                        "type" => "credit_card",
-                        "token" => "<CARD_TOKEN>",
-                        "installments" => 1,
-                        "statement_descriptor" => "Store name",
+                    [
+                        "amount" => "1000.00",
+                        "payment_method" => [
+                            "id" => "master",
+                            "type" => "credit_card",
+                            "token" => "<CARD_TOKEN>",
+                            "installments" => 1,
+                            "statement_descriptor" => "Store name",
+                        ]
                     ]
                 ]
             ]
-        ],
-    ];
+        ];
 
         // Step 5: Create the request options, setting X-Idempotency-Key
         $request_options = new RequestOptions();