need integration tests for external web API

[sabjorn]

in this commit an issue was fixed where the data needed for a web request was no longer formatted on the webpage in the same way it was previously was. Interestingly -- it was data that was no longer required to for an API call.

This was a reminder that Bandcamp can change anything at any time.

Any page specific query selector and any API endpoint should be evaluated occasionally against the real website. This way any failure that happens can be caught early.