Set show_diff to false for auth_file

We should not show changes in output since
the password might be leaked there.

I will add a follow-up patch later in master
that cleans up testing and etc.

We need to backport this to all versions.

Change-Id: Ief909c8303d7d29dcd0c19ee4cb4974667eadbcb
(cherry picked from commit 1c072a304e)

manifests/auth_file.pp

@@ -155,6 +155,7 @@ class openstack_extras::auth_file(
     owner     => 'root',
     group     => 'root',
     mode      => '0700',
+    show_diff => false,
     tag       => ['openrc'],
     content   => template('openstack_extras/openrc.erb')
   }