tools: bash from env

Use of hardcoded bash prevents users from using an upgraded bash which may
live in a different location. This behavior is often seen on OSX systems.

Utilize env to find the preferred bash to call for scripts.

scripts/check-setup.sh

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

scripts/clang-format.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 #
 # Script to clang-format suricata C code changes
 #

scripts/setup-decoder.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 #
 # Script to setup a new decoder.
 # Written by Victor Julien <victor@inliniac.net>

scripts/setup-simple-detect.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 #
 # Script to setup a new 'simple' detect module.
 # Written by Victor Julien <victor@inliniac.net>

scripts/setup-simple-detect2.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 #
 # Script to setup a new 'simple' detect module.
 # Written by Victor Julien <victor@inliniac.net>