ref(langchain): Remove redundant docstring from on_llm_start

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: ericapisani

sentry_sdk/integrations/langchain.py

@@ -351,7 +351,6 @@ def on_llm_start(
         metadata: "Optional[Dict[str, Any]]" = None,
         **kwargs: "Any",
     ) -> "Any":
-        """Run when LLM starts running."""
         with capture_internal_exceptions():
             if not run_id:
                 return