Memory leak: Catch error and retry

Refs https://redmine.teklia.com/issues/8765

dan/ocr/manager/training.py

@@ -690,7 +690,8 @@ class GenericTrainingManager:
                         for key, values in batch_data.items()
                     },
                 ]:
-                    self.zero_optimizers()
+                    with autocast(enabled=False):
+                        self.zero_optimizers()
 
                     # Set models trainable
                     for model_name in self.models: