Fix https://github.com/huggingface/peft/issues/1974#issue-2437471248

The issue is also posted at https://github.com/THUDM/GLM-4/issues/493. `THUDM/glm-4-9b-chat` uses custom code, which is not compatible with PromptEncoder. As the error indicates, this line fails:

> batch_size, seq_length = input_ids.shape
> AttributeError: 'NoneType' object has no attribute 'shape'

This is because the prompt encoder does not pass input_ids, instead passing the inputs_embeds directly. I could patch the issue by using inputs_embeds instead by editing this line:

https://huggingface.co/THUDM/glm-4-9b-chat/blob/c24133cef34ff7a7010f1e97c113effdead0966b/modeling_chatglm.py#L875

```python
if input_ids is not None:
batch_size, seq_length = input_ids.shape
else:
batch_size, seq_length, _ = inputs_embeds.shape
```

modeling_chatglm.py

@@ -872,7 +872,10 @@ class ChatGLMModel(ChatGLMPreTrainedModel):
         use_cache = use_cache if use_cache is not None else self.config.use_cache
         return_dict = return_dict if return_dict is not None else self.config.use_return_dict
 
-        batch_size, seq_length = input_ids.shape
+        if input_ids is not None:
+            batch_size, seq_length = input_ids.shape
+        else:
+            batch_size, seq_length, _ = inputs_embeds.shape
 
         if inputs_embeds is None:
             inputs_embeds = self.embedding(input_ids)