[rubygem-addressable] Fix build issue disable one test due to DNS lookup not available on koji mock builders

[Shawn Starr]

commit 668bfa22286a4a3de1969b9cd9bfbbb2ec316bf2
Author: Shawn Starr <shawn.starr at rogers.com>
Date:   Fri Aug 24 22:24:48 2012 -0400

    Fix build issue disable one test due to DNS lookup not available on koji mock builders