test: use template string for concatenation

PR-URL: #16918
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Daniel Bevenius <daniel.bevenius@gmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: Franziska Hinkelmann <franziska.hinkelmann@gmail.com>

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

@@ -46,18 +46,18 @@ function runURLSettersTests(all_test_cases) {
     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 +
-                 " = '" + test_case.new_value + "'";
+      var name = `Setting <${test_case.href}>.${attribute_to_be_set}` +
+                 ` = '${test_case.new_value}'`;
       if ("comment" in test_case) {
-        name += " " + test_case.comment;
+        name += ` ${test_case.comment}`;
       }
       test(function() {
         var url = new URL(test_case.href);
         url[attribute_to_be_set] = test_case.new_value;
         for (var attribute in test_case.expected) {
           assert_equals(url[attribute], test_case.expected[attribute])
         }
-      }, "URL: " + name)
+      }, `URL: ${name}`);
       // test(function() {
       //   var url = document.createElement("a");
       //   url.href = test_case.href;
@@ -93,15 +93,15 @@ startURLSettersTests()
       let name = `Setting <${testCase.href}>.${attributeToBeSet}` +
                  ` = "${testCase.new_value}"`;
       if ('comment' in testCase) {
-        name += ' ' + testCase.comment;
+        name += ` ${testCase.comment}`;
       }
       test(function() {
         const url = new URL(testCase.href);
         url[attributeToBeSet] = testCase.new_value;
         for (const attribute in testCase.expected) {
           assert_equals(url[attribute], testCase.expected[attribute]);
         }
-      }, 'URL: ' + name);
+      }, `URL: ${name}`);
     }
   }
 }