fix: basemodel.predict_step (#672)

## Description
We don't want to apply truncation in predict_step.

## What problem does this change solve?
Bug breaking code when gather_out=True in predict_step.

## What issue or task does this change relate to?
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Author: japols

models/src/anemoi/models/models/base.py

@@ -228,6 +228,6 @@ def predict_step(
 
             # Gather output if needed
             if gather_out and model_comm_group is not None:
-                y_hat = gather_tensor(y_hat, -2, self.truncation(y_hat, -2, grid_shard_shapes), model_comm_group)
+                y_hat = gather_tensor(y_hat, -2, grid_shard_shapes, model_comm_group)
 
         return y_hat