Switch scripts to use bash instead of sh

It's proving brittle to test because these sh scripts
keep working on my mac and failing in CI. I'm hoping
bash is going to be more consistent.

Author: gulachek

script/install-gtest.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/bin/bash
 
 set -x
 set -e

script/parse-validate-version.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/bin/bash
 
 if [ ! -f package.json ]; then
 	echo "Please run $0 from project root!"

script/test-release.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/bin/bash
 
 set -e
 set -x

script/upload-package.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/bin/bash
 
 set -e
 set -x

script/util.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/bin/bash
 
 md() {
 	if [ ! -d "$1" ]; then