Update helm to 2.14.2, which helps pass lint on newer patchsets

Update shell scripts to pass newer shellcheck

Change-Id: I19f614368a51c338a01cc1f98f874cf2df4e8b06
diff --git a/openstack-helm/openstack-helm-dev-setup.sh b/openstack-helm/openstack-helm-dev-setup.sh
index 7740689..cb383bf 100755
--- a/openstack-helm/openstack-helm-dev-setup.sh
+++ b/openstack-helm/openstack-helm-dev-setup.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 #
 # Copyright 2017-present Open Networking Foundation
 #
@@ -44,7 +44,7 @@
 then
   cd ~
   git clone https://git.openstack.org/openstack/openstack-helm-infra.git -b "${OPENSTACK_HELM_INFRA_BRANCH}"
-  if [ ! -z "${OPENSTACK_HELM_INFRA_COMMIT}" ]
+  if [ -n "${OPENSTACK_HELM_INFRA_COMMIT}" ]
   then
     cd openstack-helm-infra
     git reset --hard "${OPENSTACK_HELM_INFRA_COMMIT}"
@@ -55,7 +55,7 @@
 then
   cd ~
   git clone https://git.openstack.org/openstack/openstack-helm.git -b "${OPENSTACK_HELM_BRANCH}"
-  if [ ! -z "${OPENSTACK_HELM_COMMIT}" ]
+  if [ -n "${OPENSTACK_HELM_COMMIT}" ]
   then
     cd openstack-helm
     git reset --hard "${OPENSTACK_HELM_COMMIT}"