tools/lesspipe: Allow generic shell (#2255)

tools/lesspipe: Allow generic shell
diff --git a/tools/lesspipe/spirv-lesspipe.sh b/tools/lesspipe/spirv-lesspipe.sh
index 81e3355..57684a2 100644
--- a/tools/lesspipe/spirv-lesspipe.sh
+++ b/tools/lesspipe/spirv-lesspipe.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env sh
 # Copyright (c) 2016 The Khronos Group Inc.
 
 # Licensed under the Apache License, Version 2.0 (the "License");