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

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xarray/tests/test_conventions.py

@@ -143,7 +143,6 @@ def test_missing_fillvalue(self) -> None:
         with pytest.warns(Warning, match="floating point data as an integer"):
             conventions.encode_cf_variable(v)
 
-
     def test_multidimensional_coordinates(self) -> None:
         # regression test for GH1763
         # Set up test case with coordinates that have overlapping (but not