Update QUnit to v2.4.1.

package.json

@@ -51,7 +51,7 @@
     "node-qunit-phantomjs": "^2.0.1",
     "nodeunit": "^0.11.3",
     "nyc": "^13.1.0",
-    "qunitjs": "1.23.1",
+    "qunitjs": "^2.4.1",
     "rewire": "^4.0.1",
     "sinon": "^7.2.2"
   },

test/fixtures/generic-qunit.js

@@ -16,10 +16,10 @@
     QUnit.test(window.location.pathname, function (assert) {
         // Remove checkboxes QUnit dynamically adds to the DOM as part of its UI,
         // because these checkboxes do not comply with some Bootlint checks.
-        $('.qunit-filter').remove();
+        $('.qunit-filter, #qunit-modulefilter, #qunit-abort-tests-button').remove();
 
         assert.expect(1);
-        var lints = Array.prototype.slice.call(document.querySelectorAll('#bootlint>li'));
+        var lints = Array.prototype.slice.call(document.querySelectorAll('#bootlint > li'));
         var expectedLintMsgs = lints.map(function (item) {
             return item.dataset.lint;
         });