[ticket/15471] Add core events to ACP when pruning a forum

PHPBB3-15471

phpBB/adm/style/acp_prune_forums.html

@@ -94,7 +94,9 @@
 		<dd><label><input type="radio" class="radio" name="prune_sticky" value="1" /> {L_YES}</label>
 			<label><input type="radio" class="radio" id="sticky" name="prune_sticky" value="0" checked="checked" /> {L_NO}</label></dd>
 	</dl>
-	
+
+	<!-- EVENT acp_prune_forums_settings_append -->
+
 	<p class="quick">
 		{S_HIDDEN_FIELDS}
 		{S_FORM_TOKEN}