[VOL-2842] updates test groovy scripts

Change-Id: I981ccdf3263faef8f4e8c1af5f3740a493138e03
diff --git a/jjb/pipeline/voltha-physical-functional-tests.groovy b/jjb/pipeline/voltha-physical-functional-tests.groovy
index e47d14f..038d89c 100644
--- a/jjb/pipeline/voltha-physical-functional-tests.groovy
+++ b/jjb/pipeline/voltha-physical-functional-tests.groovy
@@ -56,7 +56,7 @@
           )
         sh returnStdout: false, script: """
         cd voltha
-        git clone -b ${branch} ${cordRepoUrl}/cord-tester
+        git clone -b master ${cordRepoUrl}/cord-tester
         mkdir -p $WORKSPACE/bin
         bash <( curl -sfL https://raw.githubusercontent.com/boz/kail/master/godownloader.sh) -b "$WORKSPACE/bin"
         cd $WORKSPACE