Reduce naming service request interval when failing to get response from headnode so that Linux compute nodes could appear in a shorter time after ARM template deployment finishes

nodemanager/core/NamingClient.cpp

@@ -108,6 +108,6 @@ void NamingClient::RequestForServiceLocation(const std::string& serviceName, std
 
         sleep(interval);
         interval *= 2;
-        if (interval > 300) interval = 300;
+        if (interval > 60) interval = 60;
     }
 }