Resolve "Ultranest failing"

Fixes (hopefully) #552 (closed)

test/core/sampler/ultranest_test.py

@@ -44,7 +44,7 @@ class TestUltranest(unittest.TestCase):
             log_interval=None,
             dlogz=None,
             max_iters=None,
-            update_interval_iter_fraction=0.2,
+            update_interval_volume_fraction=0.2,
             viz_callback=None,
             dKL=0.5,
             frac_remain=0.01,
@@ -79,7 +79,7 @@ class TestUltranest(unittest.TestCase):
             log_interval=None,
             dlogz=None,
             max_iters=None,
-            update_interval_iter_fraction=0.2,
+            update_interval_volume_fraction=0.2,
             viz_callback=None,
             dKL=0.5,
             frac_remain=0.01,