Fix unittest

sample/replication/tests/replication_test_master.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/usr/bin/env bash
 
 . /env-data.sh
 

sample/replication/tests/replication_test_slave.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/usr/bin/env bash
 
 . /env-data.sh