fix finetune batch size (#2457)

* fix batch_size, test=tts

examples/other/tts_finetune/tts3/local/finetune.py

@@ -131,10 +131,10 @@ def train_sp(args, config):
         converters=converters, )
 
     # collate function and dataloader
-
+    train_batch_size = min(len(train_metadata), config.batch_size)
     train_sampler = DistributedBatchSampler(
         train_dataset,
-        batch_size=config.batch_size,
+        batch_size=train_batch_size,
         shuffle=True,
         drop_last=True)