Silence successful elasticsearch runs

java7-runtime-headless is an empty package that can never be
installed, so it attempts to install every time. Replace it with
openjdk-7-jre-headless, which is the real package.

Also, add a refreshonly on the exec for checking the diff, because
it runs every time as well.

Change-Id: I5195d27ae90cd7f9f3e20d92aca43d7b8d0e504a
Merge "Silence successful elasticsearch runs"