[ONOS-7756] Use 1.13 TestON branch for testing with onos-1.13 and earlier branches

Change-Id: I92609cd1e691f8f375c109d51ae03facecdde1ed
diff --git a/TestON/JenkinsFile/dependencies/TriggerFuncs.groovy b/TestON/JenkinsFile/dependencies/TriggerFuncs.groovy
index a557fb4..31b9e1b 100644
--- a/TestON/JenkinsFile/dependencies/TriggerFuncs.groovy
+++ b/TestON/JenkinsFile/dependencies/TriggerFuncs.groovy
@@ -103,7 +103,7 @@
     println jobOn + "-pipeline-" + manuallyRun ? "manually" : branch
     def wiki = branch
     branch = funcs.branchWithPrefix( branch )
-    test_branch = "master"
+    test_branch = "onos-1.13"
     node( "TestStation-" + nodeName + "s" ) {
         envSetup( branch, test_branch, onosTag, jobOn, manuallyRun )
         exportEnvProperty( branch, test_branch, wiki, tests, post_result, manuallyRun, onosTag, isOldFlow )