Use a universal shebang

Fixes #15037

apps/files_external/tests/env/start-amazons3-ceph.sh

-#!/bin/bash
+#!/usr/bin/env bash
 #
 # ownCloud
 #

apps/files_external/tests/env/start-ftp-morrisjobke.sh

-#!/bin/bash
+#!/usr/bin/env bash
 #
 # ownCloud
 #

apps/files_external/tests/env/start-sftp-atmoz.sh

-#!/bin/bash
+#!/usr/bin/env bash
 #
 # ownCloud
 #

apps/files_external/tests/env/start-smb-silvershell.sh

-#!/bin/bash
+#!/usr/bin/env bash
 #
 # ownCloud
 #

apps/files_external/tests/env/start-smb-windows.sh

-#!/bin/bash
+#!/usr/bin/env bash
 #
 # ownCloud
 #

apps/files_external/tests/env/start-webdav-ownCloud.sh

-#!/bin/bash
+#!/usr/bin/env bash
 #
 # ownCloud
 #

apps/files_external/tests/env/stop-amazons3-ceph.sh

-#!/bin/bash
+#!/usr/bin/env bash
 #
 # ownCloud
 #

apps/files_external/tests/env/stop-ftp-morrisjobke.sh

-#!/bin/bash
+#!/usr/bin/env bash
 #
 # ownCloud
 #

apps/files_external/tests/env/stop-sftp-atmoz.sh

-#!/bin/bash
+#!/usr/bin/env bash
 #
 # ownCloud
 #

apps/files_external/tests/env/stop-smb-silvershell.sh

-#!/bin/bash
+#!/usr/bin/env bash
 #
 # ownCloud
 #

apps/files_external/tests/env/stop-smb-windows.sh

-#!/bin/bash
+#!/usr/bin/env bash
 #
 # ownCloud
 #

apps/files_external/tests/env/stop-webdav-ownCloud.sh

-#!/bin/bash
+#!/usr/bin/env bash
 #
 # ownCloud
 #

autotest-external.sh

-#!/bin/bash
+#!/usr/bin/env bash
 #
 # ownCloud
 #

autotest-js.sh

-#!/bin/bash
+#!/usr/bin/env bash
 #
 # ownCloud
 #

autotest.sh

-#!/bin/bash
+#!/usr/bin/env bash
 #
 # ownCloud
 #

buildjsdocs.sh

-#!/bin/bash
+#!/usr/bin/env bash
 #
 # ownCloud
 #

core/img/image-optimization.sh

-#!/bin/bash
+#!/usr/bin/env bash
 
 function recursive_optimize_images() {
 cd $1;

l10n/rm-old.sh

-#!/bin/bash
+#!/usr/bin/env bash
 
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