Fix issue number for 4176

Author: timsong-cpp

xml/issue4176.xml

@@ -1,7 +1,7 @@
 <?xml version='1.0' encoding='utf-8' standalone='no'?>
 <!DOCTYPE issue SYSTEM "lwg-issue.dtd">
 
-<issue num="4174" status="New">
+<issue num="4176" status="New">
 <title>Refer back to container requirements when extending them</title>
 <section><sref ref="[containers]"/></section>
 <submitter>Jonathan Wakely</submitter>