Disable excessive reporting

[jaraco]

At some point, the Setuptools project opted to report more than the defaults from pytest. I believe when those settings were adopted, they would provide summaries at the end of the tests showing which tests were skipped, xfailed, or xpassed. But now, what happens is if there's any failure in the test suite, the xfailures are reported in full glory, meaning one has to scroll up past many many xfailures to find the world's tiniest failure triggering all of that output. It also leads to confusion such as in this review where the user is attempting to aid in diagnosing the issue, but they don't know to search for the needle in the haystack, so stumble on a seemingly salient failure that's actually an xfailure.

Let's just rely on the pytest defaults and developers can add -rsxX if they want these details.