Fix status_url section in zuul.conf-sample

The status_url needs to be in the [webapp] section

Change-Id: I1568d7e6e62682bfca87979fc71db5648f1ed72e
diff --git a/etc/zuul.conf-sample b/etc/zuul.conf-sample
index 9b8406c..e6375a5 100644
--- a/etc/zuul.conf-sample
+++ b/etc/zuul.conf-sample
@@ -13,9 +13,6 @@
 ;ssl_cert=/path/to/server.pem
 ;ssl_key=/path/to/server.key
 
-[zuul]
-status_url=https://zuul.example.com/status
-
 [scheduler]
 tenant_config=/etc/zuul/main.yaml
 log_config=/etc/zuul/logging.conf
@@ -40,6 +37,7 @@
 [webapp]
 listen_address=0.0.0.0
 port=8001
+status_url=https://zuul.example.com/status
 
 [connection gerrit]
 driver=gerrit