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

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Author: pre-commit-ci[bot]

tests/v4/test_xgrid.py

@@ -7,7 +7,7 @@
 from numpy.testing import assert_allclose
 
 from parcels._datasets.structured.generic import X, Y, Z, datasets
-from parcels.xgrid import XGrid, _drop_field_data, _search_1d_array, _transpose_xfield_data_to_tzyx
+from parcels.xgrid import XGrid, _search_1d_array, _transpose_xfield_data_to_tzyx
 from tests import utils
 
 GridTestCase = namedtuple("GridTestCase", ["ds", "attr", "expected"])