change var to let to match ES6 standart

src/resume.html

@@ -5,7 +5,7 @@
         <meta charset="utf-8" />
         <link rel="stylesheet" href="standalone_page.css" />
         <script>
-            var data = {
+            let data = {
                 ip: '127.0.0.1'
             }
         </script>