chore: ugrade DOMPurify from v3.0.8 to 3.1.2

This incluces v3.1.1, which says:
> Note that this is a security release and should be upgraded to immediately.

https://github.com/cure53/DOMPurify/releases/tag/3.1.1

The release notes of the actual version itself are https://github.com/cure53/DOMPurify/releases/tag/3.1.2

I do not found more information on the vulnerability that apparently is in there.

* [x] manually tested and works

tpl/bootstrap.php

@@ -71,7 +71,7 @@ if ($MARKDOWN) :
 <?php
 endif;
 ?>
-		<script type="text/javascript" data-cfasync="false" src="js/purify-3.0.8.js" integrity="sha512-wWBDKh5wYGtJ1Df+PPZIn59jHVBnJ4/Yb2W/pVnzaXab8cmlZnHVx+FEBGu5JX39s3P2Qlt+aNQou0XnjW86hg==" crossorigin="anonymous"></script>
+		<script type="text/javascript" data-cfasync="false" src="js/purify-3.1.2.js" integrity="ACxShb8rPoRdC5T8NYnTbhgZx7MOKtSDUPDr0MzJiJGW1jyVxHpibsl7NYt6ahfX7lhA8/+Uc4ckF4AQmmxeUw==" crossorigin="anonymous"></script>
 		<script type="text/javascript" data-cfasync="false" src="js/legacy.js?<?php echo rawurlencode($VERSION); ?>" integrity="sha512-LYos+qXHIRqFf5ZPNphvtTB0cgzHUizu2wwcOwcwz/VIpRv9lpcBgPYz4uq6jx0INwCAj6Fbnl5HoKiLufS2jg==" crossorigin="anonymous"></script>
 		<script type="text/javascript" data-cfasync="false" src="js/privatebin.js?<?php echo rawurlencode($VERSION); ?>" integrity="sha512-I0F8qtFtaBvVvTThlXa63q0fLptZHP+hg9SbUqZ/qpimAPvHYGFfRj06aqEvECByNgKlQOWab3p8NQ2waDZ+fQ==" crossorigin="anonymous"></script>
 		<!-- icon -->

tpl/page.php

@@ -49,7 +49,7 @@ if ($MARKDOWN):
 <?php
 endif;
 ?>
-		<script type="text/javascript" data-cfasync="false" src="js/purify-3.0.8.js" integrity="sha512-wWBDKh5wYGtJ1Df+PPZIn59jHVBnJ4/Yb2W/pVnzaXab8cmlZnHVx+FEBGu5JX39s3P2Qlt+aNQou0XnjW86hg==" crossorigin="anonymous"></script>
+		<script type="text/javascript" data-cfasync="false" src="js/purify-3.1.2.js" integrity="ACxShb8rPoRdC5T8NYnTbhgZx7MOKtSDUPDr0MzJiJGW1jyVxHpibsl7NYt6ahfX7lhA8/+Uc4ckF4AQmmxeUw==" crossorigin="anonymous"></script>
 		<script type="text/javascript" data-cfasync="false" src="js/legacy.js?<?php echo rawurlencode($VERSION); ?>" integrity="sha512-LYos+qXHIRqFf5ZPNphvtTB0cgzHUizu2wwcOwcwz/VIpRv9lpcBgPYz4uq6jx0INwCAj6Fbnl5HoKiLufS2jg==" crossorigin="anonymous"></script>
 		<script type="text/javascript" data-cfasync="false" src="js/privatebin.js?<?php echo rawurlencode($VERSION); ?>" integrity="sha512-I0F8qtFtaBvVvTThlXa63q0fLptZHP+hg9SbUqZ/qpimAPvHYGFfRj06aqEvECByNgKlQOWab3p8NQ2waDZ+fQ==" crossorigin="anonymous"></script>
 		<!-- icon -->