change the window size default to 120

Change the window size default to 120 rather than 1.

Change-Id: Iffe843acd3966ac7a723a0969c791282e0f8c31c
Signed-off-by: Jagpal Singh Gill <paligill@gmail.com>
diff --git a/health_metric_config.hpp b/health_metric_config.hpp
index 89fecdc..d3279eb 100644
--- a/health_metric_config.hpp
+++ b/health_metric_config.hpp
@@ -84,7 +84,7 @@
 
     struct defaults
     {
-        static constexpr auto windowSize = 1;
+        static constexpr auto windowSize = 120;
         static constexpr auto path = "";
         static constexpr auto hysteresis = 1.0;
     };