test: replace var with const/let in test/parallel/test-whatwg-url-setters.js

Refs: nodejs/code-and-learn#97

Author: peze

test/parallel/test-whatwg-url-setters.js

@@ -37,22 +37,22 @@ function startURLSettersTests() {
 }
 
 function runURLSettersTests(all_test_cases) {
-  for (var attribute_to_be_set in all_test_cases) {
+  for (const attribute_to_be_set in all_test_cases) {
     if (attribute_to_be_set == "comment") {
       continue;
     }
-    var test_cases = all_test_cases[attribute_to_be_set];
-    for(var i = 0, l = test_cases.length; i < l; i++) {
-      var test_case = test_cases[i];
-      var name = `Setting <${test_case.href}>.${attribute_to_be_set}` +
+    const test_cases = all_test_cases[attribute_to_be_set];
+    for(let i = 0, l = test_cases.length; i < l; i++) {
+      const test_case = test_cases[i];
+      let name = `Setting <${test_case.href}>.${attribute_to_be_set}` +
                  ` = '${test_case.new_value}'`;
       if ("comment" in test_case) {
         name += ` ${test_case.comment}`;
       }
       test(function() {
-        var url = new URL(test_case.href);
+        const url = new URL(test_case.href);
         url[attribute_to_be_set] = test_case.new_value;
-        for (var attribute in test_case.expected) {
+        for (const attribute in test_case.expected) {
           assert_equals(url[attribute], test_case.expected[attribute])
         }
       }, `URL: ${name}`);