[SD3] train_dreambooth_sd3.py --train_text_encoder fails

### Describe the bug

`encode_prompt()` is called with a parameter that is not defined in code (`text_input_ids_list`)

### Reproduction

`accelerate launch train_dreambooth_sd3.py [args] --train_text_encoder`

### Logs

```shell
Traceback (most recent call last):
File "/root/diffusers/examples/dreambooth/train_dreambooth_sd3.py", line 1760, in
main(args)
File "/root/diffusers/examples/dreambooth/train_dreambooth_sd3.py", line 1546, in main
prompt_embeds, pooled_prompt_embeds = encode_prompt(
TypeError: encode_prompt() got an unexpected keyword argument 'text_input_ids_list'
```

### System Info

- 🤗 Diffusers version: 0.29.0.dev0
- Platform: Linux-6.5.0-28-generic-x86_64-with-glibc2.35
- Running on a notebook?: No
- Running on Google Colab?: No
- Python version: 3.10.14
- PyTorch version (GPU?): 2.3.1 (True)
- Flax version (CPU?/GPU?/TPU?): not installed (NA)
- Jax version: not installed
- JaxLib version: not installed
- Huggingface_hub version: 0.23.3
- Transformers version: 4.41.2
- Accelerate version: 0.31.0
- PEFT version: 0.11.1
- Bitsandbytes version: not installed
- Safetensors version: 0.4.3
- xFormers version: not installed
- Accelerator: NVIDIA A100-SXM4-80GB, 81920 MiB VRAM
- Using GPU in script?: Yes
- Using distributed or parallel set-up in script?: No

### Who can help?

@sayakpaul

Öffne examples/dreambooth/train_dreambooth_sd3.py und prüfe die Definition von encode_prompt zusammen mit ihrem Aufruf etwa bei Zeile 1546. Führe den gemeldeten accelerate launch-Befehl mit --train_text_encoder aus und verifiziere anschließend, dass das Skript nicht mehr den Fehler „unexpected keyword argument“ auslöst.

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