Schedule changes for testing onos-1.15

Change-Id: I90e3896f7008c48b160c7f2b4d9d8804a16ce2c6
diff --git a/TestON/JenkinsFile/FabricJenkinsfileTrigger b/TestON/JenkinsFile/FabricJenkinsfileTrigger
index 139c72e..f5a7dc2 100644
--- a/TestON/JenkinsFile/FabricJenkinsfileTrigger
+++ b/TestON/JenkinsFile/FabricJenkinsfileTrigger
@@ -30,7 +30,7 @@
 
 // set the versions of the onos.
 current_version = "master"
-previous_version = "1.13"
+previous_version = "1.15"
 before_previous_version = "1.14"
 
 // Function that will initialize the configuration of the Fabric.