Revert "Remove br-tun check from beaker"

This reverts commit d5cc8d3eaa.

Change-Id: I411b1a1e1e55fc13c7b376d63893a93c6537e6b9
Depends-On: https://review.openstack.org/#/c/648737/

spec/acceptance/basic_neutron_spec.rb

@@ -28,8 +28,7 @@ describe 'basic neutron' do
       it 'should list OVS bridges' do
         shell("ovs-vsctl show") do |r|
           expect(r.stdout).to match(/br-int/)
-          # TODO(aschultz): renable this after timeout is sorted
-          #expect(r.stdout).to match(/br-tun/)
+          expect(r.stdout).to match(/br-tun/)
         end
       end
     end