Auto merge of #28507 - yvt:fix-shebang, r=jdm

Use `#!/usr/bin/env bash` in shell scripts for NixOS compatibility

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This PR updates the shebang lines of shell scripts for NixOS compatibility.

---
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- [ ] These changes fix #___ (GitHub issue number if applicable)

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- [ ] There are tests for these changes OR
- [x] These changes do not require tests because it only updates development tools

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etc/jsdefine

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 #
 # Handy tool for extracting #defines from jsapi.h.  For example:
 #     ./jsdefine %x JSCLASS_GLOBAL_FLAGS

etc/rustdoc-with-private

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 # Emit documentation for private items so it is easier to look
 # up internal definitions.

etc/taskcluster/mock.py

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 # Copyright 2018 The Servo Project Developers. See the COPYRIGHT
 # file at the top-level directory of this distribution.

etc/taskcluster/simulate_github_events.py

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this

python/tidy/servo_tidy_tests/shell_tidy.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 #
 # Tests tidy for shell scripts.
 

support/android/openssl.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 # Cross-compile environment for Android on ARMv7 and x86
 #
 # Contents licensed under the terms of the OpenSSL license