nix develop is failing an ANI distance test?!

[ctb]

Over in #3105, a PR which doesn't change anything about nix:

% nix develop --command bash -c "tox -e py310"

yields:

 =================================== FAILURES ===================================
___________________ test_containment_to_distance_confidence ____________________
[gw2] darwin -- Python 3.10.13 /Users/runner/work/sourmash/sourmash/.tox/py310/bin/python

    def test_containment_to_distance_confidence():
        contain = 0.1
        scaled = 100
        nkmers = 10000
        ksize = 31
        confidence = 0.99
        res = containment_to_distance(
            contain,
            ksize,
            scaled,
            confidence=confidence,
            n_unique_kmers=nkmers,
            estimate_ci=True,
        )
        print(res)
        # check results
        assert res.dist == 0.07158545548052564
        assert res.dist_low == 0.04802880300938562
        assert res.dist_high == 0.09619930040790341
        assert res.p_exceeds_threshold == False
        confidence = 0.90
        res2 = containment_to_distance(
            contain,
            ksize,
            scaled,
            n_unique_kmers=nkmers,
            confidence=confidence,
            estimate_ci=True,
        )
        print(res2)
        # check results
        assert res2.dist == res.dist
>       assert res2.dist_low == 0.05599435479247415
E       assert 0.05599435479247409 == 0.05599435479247415
E        +  where 0.05599435479247409 = ciANIResult(dist=0.07158545548052564, p_nothing_in_common=4.3171247410658655e-05, p_threshold=0.001, size_is_inaccurate=False, p_exceeds_threshold=False, dist_low=0.05599435479247409, dist_high=0.08758718871990222).dist_low

tests/test_distance_utils.py:255: AssertionError

[ctb]

specifically,

E       assert 0.05599435479247409 == 0.05599435479247415

which I will fix with a round.