few components with rspec3 syntax

spec/components/discourse_hub_spec.rb

@@ -6,7 +6,7 @@ describe DiscourseHub do
     it 'should return just return the json that the hub returns' do
       hub_response = {'success' => 'OK', 'latest_version' => '0.8.1', 'critical_updates' => false}
       RestClient.stubs(:get).returns( hub_response.to_json )
-      DiscourseHub.discourse_version_check.should == hub_response
+      expect(DiscourseHub.discourse_version_check).to eq(hub_response)
     end
   end
 end