Bash is not necessarily in /bin/bash

[Kernald]

In this helper:

rules_android/rules/android_sdk_repository/helper.bzl

Lines 288 to 315 in 045b998

	for tool in ["aapt", "aapt2", "aidl", "zipalign"]:
	native.genrule(
	name = tool + "_runner",
	srcs = [],
	outs = [tool + "_runner.sh"],
	cmd = "\n".join([
	"cat > $@ << 'EOF'",
	"#!/bin/bash",
	"set -eu",
	# The tools under build-tools/VERSION require the libraries under
	# build-tools/VERSION/lib, so we can't simply depend on them as a
	# file like we do with aapt.
	# On Windows however we can use these binaries directly because
	# there's no runfiles support so Bazel just creates a junction to
	# {SDK}/build-tools.
	"SDK=$${0}.runfiles/%s" % name,
	# If $${SDK} is not a directory, it means that this tool is running
	# from a runfiles directory, in the case of
	# android_instrumentation_test. Hence, use the androidsdk
	# that's already present in the runfiles of the current context.
	"if [[ ! -d $${SDK} ]] ; then",
	" SDK=$$(pwd)/../%s" % name,
	"fi",
	"tool=$${SDK}/build-tools/%s/%s" % (build_tools_directory, tool),
	"exec env LD_LIBRARY_PATH=$${SDK}/build-tools/%s/lib64 $$tool $$*" % build_tools_directory,
	"EOF\n",
	]),
	)

Bash is hard-coded in /bin/bash, which is not portable - e.g. NixOS doesn't have it there. Relying on e.g. /usr/bin/env bash instead would be more portable.