They seem to be barfing up inside the histogram tests, I would assume this one:
@requires_memory(free_bytes=1e10)
@pytest.mark.slow
def test_big_arrays(self):
...
due to hitting a memory limit. I would think memory limitations mean that the test should just never be run on CI.
I doubt that there is anything to worry about or that anything concretely changed. But am not sure how to avoid CI to run into it.