tests: add tests for plugins version. (#28366)

js/tests/unit/alert.js

@@ -116,13 +116,8 @@ $(function () {
     assert.ok(Alert._getInstance($alert[0]) === null)
   })
 
-  QUnit.test('should return alert version', function (assert) {
+  QUnit.test('should return the version', function (assert) {
     assert.expect(1)
-
-    if (typeof Alert !== 'undefined') {
-      assert.ok(typeof Alert.VERSION === 'string')
-    } else {
-      assert.notOk()
-    }
+    assert.strictEqual(typeof Alert.VERSION, 'string')
   })
 })