text: Title: Upload to HF fails for non-LLM trained
  Body: **Describe the bug**
  When a model is trained for categories/classification, the model weights are saved a `file` called `model/model_weights`. If the model is trained with type llm instead, the weights are saved to the **directory** `model/model_weights` with contents `README.md`, `adapter_config.json`, `adapter_model.bin`.
  
  
  **To Reproduce**
  Steps to reproduce the behavior:
  
  1. Train a model with name `MODEL_NAME=bug-reprod-model` and config
  
  ```
  {
      "input_features": [
          {
              "name": "text",
              "type": "text",
              "encoder": {
                  "trainable": true,
                  "pretrained_model_name_or_path": "meta-llama/Llama-2-7b-hf",
                  "adapter": {
                      "type": "lora"
                  }
              }
          }
      ],
  
      "output_features": [
          {
              "name": "label",
              "type": "category"
          }
      ]
  }
  ```
  2. Attempt to uploaded the trained model for hugging face account `HF_ID=bug-reprod-hf-id`
  
  ```
  ludwig upload hf_hub -r $HF_ID/$MODEL_NAME -m $MODEL_NAME/api_experiment_$MODEL_NAME
  ```
  
  You should see an error  like this
  ![image](https://github.com/ludwig-ai/ludwig/assets/459925/e049b23e-0872-4f7e-bda5-b49cdbea00ee)
  
  3. Manually move the weights file to a directory
  ```
  pushd $MODEL_NAME/api_experiment_$MODEL_NAME/model && \
   mv model_weights adapter_model.bin && \
   mkdir model_weights && \
   mv adapter_model.bin model_weights && \
   cp ~/save/$MODEL_NAME/{adapter_config.json,README.md} model_weights && \
   popd
   ```
   
   4. The upload to HF should now be successful
   
   ```
  ludwig upload hf_hub -r $HF_ID/$MODEL_NAME -m $MODEL_NAME/api_experiment_$MODEL_NAME
  ```
  ![image](https://github.com/ludwig-ai/ludwig/assets/459925/ce5d403c-716c-436f-a0a4-685421ad77ac)
  
  
  **Expected behavior**
  The model should upload to HF without having to manually create the directory
  
  **Environment (please complete the following information):**
  
  - OS:
  Distributor ID: Ubuntu
  Description:    Ubuntu 20.04.6 LTS
  Release:        20.04
  Codename:       focal
  - Version: CUDA 11.8
  - Pytorch: 2.0.0+cu118
  - Python: 3.8.10
  - Ludwig: 0.8.1.post1
  
  **Additional context**
  Add any other context about the problem here.
  
  @arnavgarg1 