bugfix for inference prompt template

Signed-off-by: HuiyingLi <[email protected]>

nemo/collections/multimodal/data/neva/neva_dataset.py

@@ -512,7 +512,8 @@ def preprocess_nv_dpo(sources: dict, tokenizer, cfg,) -> Dict:
                 conv.append_message(turn['from'], turn['value'])
         context = conv.get_prompt()
         if strip_end_for_inference:
-            context = context.rstrip("\n<extra_id_1>") + "\n"
+            if context.endswith("\n<extra_id_1>"):
+                context = context[:-len("\n<extra_id_1>")] + "\n"
         conversations.append(context)
 
     add_extra_token = cfg.get("add_extra_token")