fix(langchain): remove empty accordion in middleware docs (#1546)

The Context editing middleware docs have an additional Configuration
options accordion. This patch fixes.

<img width="657" height="106" alt="Screenshot 2025-11-20 at 9 14 43 AM"
src="https://github.com/user-attachments/assets/76784621-a16a-4a7b-bd14-560009ba85b9"
/>

Author: christian-bromann

src/oss/langchain/middleware/built-in.mdx

@@ -1939,11 +1939,9 @@ agent = create_agent(
     ],
 )
 ```
-:::
 
 <Accordion title="Configuration options">
 
-:::python
 <ParamField body="root_path" type="str" required>
     Root directory to search. All file operations are relative to this path.
 </ParamField>
@@ -1998,10 +1996,10 @@ result = agent.invoke({
 # 1. glob_search(pattern="**/*.py") to find Python files
 # 2. grep_search(pattern="async def", include="*.py") to find async functions
 ```
-:::
-
 </Accordion>
 
+:::
+
 ## Provider-specific middleware
 
 These middleware are optimized for specific LLM providers.