Make search.elastic.version an int not a string

Summary:
Puppet is not budging in allowing me to use an int so let's just make it a int.

This fixes prod for when we want to change versions too.

Change-Id: I348d674762953433bd77c6ff8efb4246d5d68b73

Reviewers: mmodell, Dzahn

Subscribers: jenkins

Differential Revision: https://phabricator.wikimedia.org/D562