Use sudo -H -E when running pip

-E will result in pip writing to the current users disk cache, and
that prevents future non-root pip calls using it properly.

Change-Id: Ib70b3d59a20967bc7e08c70387eb7dd6f7f1b5c5

scripts/env-setup.sh

@@ -44,7 +44,7 @@ fi
 wget -O /tmp/get-pip.py https://bootstrap.pypa.io/get-pip.py
 sudo python /tmp/get-pip.py
 
-sudo -E pip install -r "$(dirname $0)/../requirements.txt"
+sudo -H -E pip install -r "$(dirname $0)/../requirements.txt"
 
 u=$(whoami)
 g=$(groups | awk '{print $1}')