Our company is using an external API that is actually in beta state. This means it's not stable at all yet, and it changes its requests/responses every week or so.
I'd like to write test to ensure my code is working. Unit tests are already done for my own code. But the API itself isn't tested, because it would violate the first rule of FIRST (Fast tests). If I test the API requests/responses 'live' (they have a sandbox version of the API), tests take around 7 seconds for themselves. That's a long time.
How could I be sure the API still uses the same structure for requests and responses in this case, is it a special case where slow tests are ok ? My hierarchy wants to use this API asap obviously, and I don't want any bug whatsoever.