add slack notification

Change-Id: I7c6f32cc27d70b1e1d790b677d988fb230144c17
diff --git a/lab-pipeline.groovy b/lab-pipeline.groovy
index 51ecd4f..044a24f 100644
--- a/lab-pipeline.groovy
+++ b/lab-pipeline.groovy
@@ -533,6 +533,9 @@
             throw e
         } finally {
 
+            // send notification
+            common.sendNotification(currentBuild.result,HEAT_STACK_NAME,["slack"])
+
             //
             // Clean
             //