Ubuntu: Check TCP port in acceptance tests

Now we deploy mistral in both CentOS and Ubuntu thus we can validate
the tcp port in Ubuntu as well.

Change-Id: I565ad3dabb621f536038447bd01ccea8a0adf146

spec/acceptance/10_basic_mistral_spec.rb

@@ -22,12 +22,8 @@ describe 'basic mistral' do
       apply_manifest(pp, :catch_changes => true)
     end
 
-    if os[:family].casecmp('RedHat') == 0
-      describe port(8989) do
-        it { is_expected.to be_listening }
-      end
+    describe port(8989) do
+      it { is_expected.to be_listening }
     end
-
   end
-
 end