Fix PHP-style array element in settings json

Author: ThiefMaster

README.md

@@ -221,8 +221,8 @@ This is the settings.json file:
         "NameIDFormat": "urn:oasis:names:tc:SAML:2.0:nameid-format:unspecified",
         // Usually x509cert and privateKey of the SP are provided by files placed at
         // the certs folder. But we can also provide them with the following parameters
-        'x509cert' => '',
-        'privateKey' => ''
+        "x509cert": "",
+        "privateKey": ""
     },
 
     // Identity Provider Data that we want connected with our SP.