scripts : make the shell scripts cross-platform (#14341)

tests/test-lora-conversion-inference.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 set -e
 
 # Array of models to iterate over

tests/test-tokenizer-0.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 #
 # Usage:
 #

tests/test-tokenizers-repo.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 if [ $# -lt 2 ]; then
     printf "Usage: $0 <git-repo> <target-folder> [<test-exe>]\n"