Knowledge graph no longer exists as a chunking method (#7382)

### What problem does this PR solve?

### Type of change

- [x] Documentation Update

docs/references/http_api_reference.md

   - `"presentation"`: Presentation
   - `"picture"`: Picture
   - `"one"`: One
-    Ensure your LLM is properly configured on the **Settings** page before selecting this. Please also note that Knowledge Graph consumes a large number of Tokens!
   - `"email"`: Email
 
 - `"parser_config"`: (*Body parameter*), `object`  
     - `"html4excel"`: Indicates whether to convert Excel documents into HTML format. Defaults to `false`.
     - `"delimiter"`: Defaults to `"\n"`.
     - `"task_page_size"`: Defaults to `12`. For PDF only.
-    - `"raptor"`: Raptor-specific settings. Defaults to: `{"use_raptor": false}`.
+    - `"raptor"`: RAPTOR-specific settings. Defaults to: `{"use_raptor": false}`.
   - If `"chunk_method"` is `"qa"`, `"manuel"`, `"paper"`, `"book"`, `"laws"`, or `"presentation"`, the `"parser_config"` object contains the following attribute:  
-    - `"raptor"`: Raptor-specific settings. Defaults to: `{"use_raptor": false}`.
+    - `"raptor"`: RAPTOR-specific settings. Defaults to: `{"use_raptor": false}`.
   - If `"chunk_method"` is `"table"`, `"picture"`, `"one"`, or `"email"`, `"parser_config"` is an empty JSON object.
 
 #### Response
     - `"html4excel"`: Indicates whether to convert Excel documents into HTML format. Defaults to `false`.
     - `"delimiter"`: Defaults to `"\n"`.
     - `"task_page_size"`: Defaults to `12`. For PDF only.
-    - `"raptor"`: Raptor-specific settings. Defaults to: `{"use_raptor": false}`.
+    - `"raptor"`: RAPTOR-specific settings. Defaults to: `{"use_raptor": false}`.
   - If `"chunk_method"` is `"qa"`, `"manuel"`, `"paper"`, `"book"`, `"laws"`, or `"presentation"`, the `"parser_config"` object contains the following attribute:
-    - `"raptor"`: Raptor-specific settings. Defaults to: `{"use_raptor": false}`.
+    - `"raptor"`: RAPTOR-specific settings. Defaults to: `{"use_raptor": false}`.
   - If `"chunk_method"` is `"table"`, `"picture"`, `"one"`, or `"email"`, `"parser_config"` is an empty JSON object.
 
 #### Response

docs/references/python_api_reference.md

     `None`
   - `chunk_method`=`"one"`:  
     `None`
-  - `chunk_method`=`"knowledge-graph"`:  
-    `{"chunk_token_num":128,"delimiter": "\\n","entity_types":["organization","person","location","event","time"]}`
   - `chunk_method`=`"email"`:  
     `None`