chore(tests): cleanup test scripts

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>

tests/lean/interactive/test_single.sh

@@ -1,6 +1,6 @@
-#!/bin/bash
+#!/usr/bin/env bash
 if [ $# -ne 3 -a $# -ne 2 ]; then
-    echo "Usage: test.sh [lean-executable-path] [file] [yes/no]?"
+    echo "Usage: test_single.sh [lean-executable-path] [file] [yes/no]?"
     exit 1
 fi
 ulimit -s unlimited

tests/lean/test.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 if [ $# -ne 2 -a $# -ne 1 ]; then
     echo "Usage: test.sh [lean-executable-path] [yes/no]?"
     exit 1

tests/lean/test_single.sh

@@ -1,6 +1,6 @@
-#!/bin/bash
+#!/usr/bin/env bash
 if [ $# -ne 3 -a $# -ne 2 ]; then
-    echo "Usage: test.sh [lean-executable-path] [file] [yes/no]?"
+    echo "Usage: test_single.sh [lean-executable-path] [file] [yes/no]?"
     exit 1
 fi
 ulimit -s 8192

tests/lean/test_single_pp.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 # Script for testing if Lean can parse the output produced by its
 # pretty printer
 if [ $# -ne 2 ]; then

tests/lua/test.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 if [ $# -ne 1 ]; then
     echo "Usage: test.sh [lean-executable-path]"
     exit 1

tests/lua/test_single.sh

@@ -1,6 +1,6 @@
-#!/bin/bash
+#!/usr/bin/env bash
 if [ $# -ne 2 ]; then
-    echo "Usage: test.sh [lean-executable-path] [file]"
+    echo "Usage: test_single.sh [lean-executable-path] [file]"
     exit 1
 fi
 ulimit -s unlimited