Switch out resolver to mitigate SocketError

Spotted in the logs:
https://gitlab.com/gitlab-com/infrastructure/issues/2387#note_39013276

The problem is the resolver, which with a require gets patched.

lib/tasks/gitlab/artifacts.rake

 require 'logger'
+require 'resolv-replace'
 
 desc "GitLab | Migrate files for artifacts to comply with new storage format"
 namespace :gitlab do