Explicitly use Bash in scripts that actually use non-POSIX features or do not have a shebang at all

.circleci/soltest.sh

@@ -1,4 +1,4 @@
-#! /bin/bash
+#!/usr/bin/env bash
 #------------------------------------------------------------------------------
 # Bash script to execute the Solidity tests by CircleCI.
 #

scripts/common_cmdline.sh

@@ -1,3 +1,4 @@
+#!/usr/bin/env bash
 # ------------------------------------------------------------------------------
 # vim:ts=4:et
 # This file is part of solidity.

scripts/docker_deploy_manual.sh

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

scripts/endToEndExtraction/create_traces.sh

@@ -1,3 +1,5 @@
+#!/usr/bin/env bash
+
 BASE_PATH="$( cd "$(dirname "$0")" >/dev/null 2>&1 || exit ; pwd -P )"
 
 mkdir -p build

scripts/install_obsolete_jsoncpp_1_7_4.sh

@@ -1,4 +1,4 @@
-#!/usr/bin/env sh
+#!/usr/bin/env bash
 set -e
 
 TEMPDIR=$(mktemp -d)

scripts/uniqueErrors.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/usr/bin/env bash
 
 REPO="$(dirname "$0")/.."