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.