How to check events unrelated to aggregates in your application?

[Controlix]

I like yout demo a lot; it clearly explains hot to mix pact with axon.

However, I do not see how you can provide the same kind of test for handling an event that is generated by an external system. That events will have no matching aggregate in our own application, so I can not use the AggregateTestFixture. There seems to be no related fixture hor event handlers.

Do you have any advice on implementing this kind of pact consumer test?