[prep-release-3.0.9] Update Changelog for 3.0.9-RC4 release.

Author: bantu

phpBB/docs/CHANGELOG.html

@@ -335,6 +335,8 @@ <h4>        Bug
 </li>
 <li>[<a href='http://tracker.phpbb.com/browse/PHPBB3-10247'>PHPBB3-10247</a>] -         mediumint(8) too small for phpbb_login_attempts.attempt_id
 </li>
+<li>[<a href='http://tracker.phpbb.com/browse/PHPBB3-10250'>PHPBB3-10250</a>] -         phpBB Logo needs the Registered Trademark Symbol
+</li>
 </ul>
 
 <h4>        Improvement