fix: indents in sample code (#3674)

Author: Yasunori

Diff for: docs/helpers/REST.md

@@ -41,7 +41,8 @@ Type: [object][4]
       endpoint: 'http://site.com/api',
       prettyPrintJson: true,
       onRequest: (request) => {
-      request.headers.auth = '123';
+        request.headers.auth = '123';
+      }
     }
   }
 }

Diff for: lib/helper/REST.js

@@ -34,7 +34,8 @@ const config = {};
  *       endpoint: 'http://site.com/api',
  *       prettyPrintJson: true,
  *       onRequest: (request) => {
- *       request.headers.auth = '123';
+ *         request.headers.auth = '123';
+ *       }
  *     }
  *   }
  *}