Remove test case for /_test500/

 - Legacy-Id: 1815

Author: pasieronen

ietf/redirects/testurl.list

@@ -5,7 +5,7 @@
 200	/googlea30ad1dacffb5e5b.html # Google webmaster tool verification page
 200	/sitemap.xml
 404	/_doesnotexist/
-skip	/_test500/
+#skip	/_test500/
 
 #301	/list/request....	# test middleware that strips periods and redirects instead of 404
 #skip	/images/ietf-icon.bmp