[train][doc] Add get_all_reported_checkpoints and ReportedCheckpoint to API docs (#56174)

Signed-off-by: Timothy Seah <tseah@anyscale.com>
Signed-off-by: Douglas Strodtman <douglas@anyscale.com>

Author: TimothySeah

doc/source/train/api/api.rst

@@ -143,6 +143,7 @@ Ray Train Utilities
     :nosignatures:
     :toctree: doc/
 
+    ~train.get_all_reported_checkpoints
     ~train.get_checkpoint
     ~train.get_context
     ~train.get_dataset_shard
@@ -165,6 +166,7 @@ Ray Train Output
     :template: autosummary/class_without_autosummary.rst
     :toctree: doc/
 
+    ~train.ReportedCheckpoint
     ~train.Result
 
 Ray Train Errors

python/ray/train/v2/api/train_fn_utils.py

@@ -192,7 +192,7 @@ def train_func(config):
 
     Returns:
         List of ReportedCheckpoint objects that represent the checkpoints and
-            corresponding metrics reported by the workers.
+        corresponding metrics reported by the workers.
     """
     return get_train_fn_utils().get_all_reported_checkpoints()