Use bash to run shell scripts

Use `bash` instead of `sh` to run shell scripts.

We would like to support Nix users who do not typically have any shell
other than `sh` at a known path, therefore use `/usr/bin/env bash`.

bitcoin/contrib/test.sh

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

bitcoin/embedded/scripts/install-deps

@@ -1,3 +1,3 @@
-#!/bin/sh
+#!/usr/bin/env bash
 
 apt install gcc-arm-none-eabi qemu-system-arm gdb-multiarch

contrib/test.sh

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

fuzz/contrib/test.sh

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

githooks/pre-commit

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/usr/bin/env bash
 #
 # Verify what is about to be committed. Called by "git commit" with no
 # arguments. The hook should exit with non-zero status after issuing an

hashes/embedded/scripts/install-deps

@@ -1,3 +1,3 @@
-#!/bin/sh
+#!/usr/bin/env bash
 
 apt install gcc-arm-none-eabi qemu-system-arm gdb-multiarch

internals/contrib/test.sh

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