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

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optim_esm_tools/region_finding/keep_all.py

@@ -2,6 +2,7 @@
 import itertools
 import numpy as np
 
+
 class MaskAll(RegionExtractor):
     def get_masks(self) -> _mask_cluster_type:  # pragma: no cover
         mask_2d = ~self.data_set[self.variable].isnull().all(dim='time')