Make shell scripts more portable by using /usr/bin/env bash

contrib/snapshot/airdrop_hush3.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 # This code inspired by and dedicated to Decker
 
 echo "Airdropping funds to HUSH3, hold onto your butts..."

contrib/snapshot/testnet_airdrop_hush3.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 # This code inspired by and dedicated to Decker
 
 echo "Airdropping funds to HUSH3, hold onto your butts..."