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

for more information, see https://pre-commit.ci

Author: pre-commit-ci[bot]

monai/losses/unified_focal_loss.py

@@ -250,7 +250,7 @@ def forward(self, y_pred: torch.Tensor, y_true: torch.Tensor) -> torch.Tensor:
 
         if y_true.shape[1] == self.num_classes:
             if not torch.all((y_true == 0) | (y_true == 1)):
-                raise ValueError(f"y_true appears to be one-hot but contains values other than 0 and 1")
+                raise ValueError("y_true appears to be one-hot but contains values other than 0 and 1")
         elif y_true.shape[1] == 1:
             if torch.max(y_true) >= self.num_classes:
                 raise ValueError(