Tests: Include the check_comment function tests in the comment group.

Adds `@group comment` notation to the `Tests_Comment_CheckComment` class. Introduced in [32519].

Props gma992.
Fixes #37356.

git-svn-id: https://develop.svn.wordpress.org/trunk@38114 602fd350-edb4-49c9-b593-d223f7449a82

tests/phpunit/tests/comment/checkComment.php

@@ -1,5 +1,8 @@
 <?php
 
+/**
+ * @group comment
+ */
 class Tests_Comment_CheckComment extends WP_UnitTestCase {
 	public function test_should_return_true_when_comment_whitelist_is_disabled() {
 		$author       = 'BobtheBuilder';