[pre-commit.ci] auto fixes from pre-commit.com hooks

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tests/test_indices.py

@@ -375,6 +375,7 @@ def test_chill_units(self, tas_series):
         out = xci.chill_units(tas, positive_only=True)
         # Only the last day contains negative chill units.
         assert out[0] == 0.5 * num_cu_05 + num_cu_1 - 0.5 * 3
+
     def test_cool_night_index(self, open_dataset):
         ds = open_dataset("cmip5/tas_Amon_CanESM2_rcp85_r1i1p1_200701-200712.nc")
         ds = ds.rename(dict(tas="tasmin"))