root: do not use /bin/bash directly (#14698)

Makefile

@@ -1,6 +1,6 @@
 .PHONY: gen dev-reset all clean test web website
 
-SHELL := /bin/bash
+SHELL := /usr/bin/env bash
 .SHELLFLAGS += ${SHELLFLAGS} -e -o pipefail
 PWD = $(shell pwd)
 UID = $(shell id -u)

scripts/test_docker.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 set -e -x -o pipefail
 hash="$(git rev-parse HEAD || openssl rand -base64 36 | sha256sum)"
 

website/scripts/docsmg/m.bash

@@ -1,2 +1,2 @@
-#!/bin/bash
+#!/usr/bin/env bash
 docsmg move $1 $2 | tee -a migratefile