BUG: Rename pretraining_run_checkpoints (#841)

"Parameter `extra_downloaded_run_id` has been renamed to
`pretraining_run_checkpoints`" (According to CHANGELOG.md) but is still
in used in SSLClassifierContainer class (in
InnerEye/ML/SSL/lightning_containers/ssl_image_classifier.py).
It will raise an AttributeError: 'SSLClassifierCIFAR' object has no
attribute 'extra_downloaded_run_id' when trying to run python
InnerEyeML/runner.py --model=CXRImageClassifier
--pretraining_run_recovery_id={THE_ID_TO_YOUR_SSL_TRAINING_JOB}.
So renamed it to `pretraining_run_checkpoints` there too.
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InnerEye/ML/SSL/lightning_containers/ssl_image_classifier.py

@@ -35,12 +35,12 @@ class SSLClassifierContainer(SSLContainer):
         This method must create the actual Lightning model that will be trained.
         """
         if self.local_ssl_weights_path is None:
-            assert self.extra_downloaded_run_id is not None
+            assert self.pretraining_run_checkpoints is not None
             try:
-                path_to_checkpoint = self.extra_downloaded_run_id.get_best_checkpoint_paths()
+                path_to_checkpoint = self.pretraining_run_checkpoints.get_best_checkpoint_paths()
             except FileNotFoundError:
                 logging.info("Best checkpoint not found - using last recovery checkpoint instead")
-                path_to_checkpoint = self.extra_downloaded_run_id.get_recovery_checkpoint_paths()
+                path_to_checkpoint = self.pretraining_run_checkpoints.get_recovery_checkpoint_paths()
             path_to_checkpoint = path_to_checkpoint[0]  # type: ignore
         else:
             path_to_checkpoint = self.local_ssl_weights_path