[stats_lettuce_fix] fix for the lettuce error: Not found statistics counter notifyoutv4

http://git.bind10.isc.org/~tester/builder//BIND10-lettuce/20120918121701-DebianLinux-x86_64-GCC/logs/lettuce.out
  AssertionError: Not found statistics counter notifyoutv4 for zone example.org.

It has to wait at least for one second since the query to
b10-stats. b10-stats doesn't request to other module, e.g. b10-xfrout,
for less than one second, even if show command is invoked via
bindctl. This is for avoiding too frequent requests to b10-stats.

tests/lettuce/features/xfrin_notify_handling.feature

@@ -44,6 +44,9 @@ Feature: Xfrin incoming notify handling
 
     A query for www.example.org to [::1]:47806 should have rcode NOERROR
 
+    # waiting for a second since the last query to Stats
+    sleep for 1 seconds
+
     #
     # Test for statistics
     #
@@ -118,6 +121,9 @@ Feature: Xfrin incoming notify handling
 
     A query for www.example.org to [::1]:47806 should have rcode NXDOMAIN
 
+    # waiting for a second since the last query to Stats
+    sleep for 1 seconds
+
     #
     # Test2 for statistics
     #