add istanbul branch for cps-review

Issue-ID: CPS-615
Signed-off-by: tragait <rahul.tyagi@est.tech>
Change-Id: I88b582deb5b09a33aa722662320af697365a3e83
diff --git a/jjb/cps/cps-csit.yaml b/jjb/cps/cps-csit.yaml
index 4c8a981..6a42b61 100644
--- a/jjb/cps/cps-csit.yaml
+++ b/jjb/cps/cps-csit.yaml
@@ -17,6 +17,8 @@
                 branch: 'master'
           - 'honolulu':
                 branch: 'honolulu'
+          - 'istanbul':
+                branch: 'istanbul'
       mvn-settings: 'cps-settings'
       robot-options: ''
       branch: 'master'