Align table heading with 'System Model Settings' (#4646)

…the 'System Model Settings'

### What problem does this PR solve?

### Type of change


- [x] Documentation Update

docs/references/supported_models.mdx

@@ -12,7 +12,7 @@ A complete list of models supported by RAGFlow, which will continue to expand.
 <APITable>
 ```
 
-| Provider              | Chat               | Embedding          | Rerank             | Multimodal         | ASR                | TTS                |
+| Provider              | Chat               | Embedding          | Rerank             | Img2txt            | Sequence2txt       | TTS                |
 | --------------------- | ------------------ | ------------------ | ------------------ | ------------------ | ------------------ | ------------------ |
 | Anthropic             | :heavy_check_mark: |                    |                    |                    |                    |                    |
 | Azure-OpenAI          | :heavy_check_mark: | :heavy_check_mark: |                    | :heavy_check_mark: | :heavy_check_mark: |                    |