Try and make zsh complain less

My turn to make "this cant possibly break" changes to the scripts.

paper

@@ -199,7 +199,7 @@ unset -f color
 unset -f colorend
 unset -f paperstash
 unset -f paperunstash
-if [ "$failed" == "1" ]; then
+if [[ "$failed" == "1" ]]; then
 	unset failed
 	false
 else

scripts/apatch.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 gitcmd="git -c commit.gpgsign=false"
 

scripts/checkoutpr.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 if [ -z "$1" ]; then
 	echo "$0 <prID>"
 	exit 1;