Use sh for docker test scripts

License: MIT
Signed-off-by: Hector Sanjuan <hector@protocol.ai>

docker/cluster-restart.sh

@@ -1,4 +1,4 @@
-#! /bin/bash
+#!/bin/sh
 
 # Restart the cluster process
 sleep 4

docker/random-killer.sh

@@ -1,4 +1,4 @@
-#! /bin/bash
+#!/bin/sh
 
 # $1=sleep time, $2=first command, $3=second command
 # Loop forever

docker/random-stopper.sh

@@ -1,4 +1,4 @@
-#! /bin/bash
+#! /bin/sh
 
 # $1=sleep time, $2=first command, $3=second command
 # Loop forever

docker/wait-killer-stopper.sh

@@ -1,4 +1,4 @@
-#! /bin/bash
+#! /bin/sh
 
 ## Wait for cluster service process to exist and the stop the
 ## killer