Pin Helm version to v2.14.3

Change-Id: I5df8563178a1b67cf943761f6f96396f38f3c499
diff --git a/jjb/pipeline/voltha-bbsim-tests.groovy b/jjb/pipeline/voltha-bbsim-tests.groovy
index df1f1a9..42b984b 100644
--- a/jjb/pipeline/voltha-bbsim-tests.groovy
+++ b/jjb/pipeline/voltha-bbsim-tests.groovy
@@ -60,6 +60,7 @@
         sh """
            git clone https://github.com/ciena/kind-voltha.git
            cd kind-voltha/
+           export DESIRED_VERSION=v2.14.3    # For Helm
            DEPLOY_K8S=y JUST_K8S=y FANCY=0 ./voltha up
            """
       }