fix: remove saving of metadata for training ckpt (ecmwf#190)

* remove saving of unused metadata for training ckpt, fixing ecmwf#57

CHANGELOG.md

@@ -12,6 +12,7 @@ Keep it human-readable, your future self will thank you!
 ### Fixed
 - Not update NaN-weight-mask for loss function when using remapper and no imputer [#178](https://github.com/ecmwf/anemoi-training/pull/178)
 - Dont crash when using the profiler if certain env vars arent set [#180](https://github.com/ecmwf/anemoi-training/pull/180)
+- Remove saving of metadata to training checkpoint [#57](https://github.com/ecmwf/anemoi-training/pull/190)
 
 ### Added
 - Introduce variable to configure: transfer_learning -> bool, True if loading checkpoint in a transfer learning setting.

src/anemoi/training/diagnostics/callbacks/checkpoint.py

@@ -173,9 +173,6 @@ def _save_checkpoint(self, trainer: pl.Trainer, lightning_checkpoint_filepath: s
         if trainer.is_global_zero:
             from weakref import proxy
 
-            # save metadata for the training checkpoint in the same format as inference
-            save_metadata(lightning_checkpoint_filepath, metadata)
-
             # notify loggers
             for logger in trainer.loggers:
                 logger.after_save_checkpoint(proxy(self))