fix: Replace langchain_classic with langchain_community

Fixed incorrect import in generate_code_node.py that was causing
ModuleNotFoundError. langchain_classic doesn't exist, should be
langchain_community.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: 2 people

scrapegraphai/nodes/generate_code_node.py

@@ -12,7 +12,7 @@
 from bs4 import BeautifulSoup
 from jsonschema import ValidationError as JSONSchemaValidationError
 from jsonschema import validate
-from langchain_classic.output_parsers.structured import (
+from langchain_community.output_parsers.structured import (
     ResponseSchema,
     StructuredOutputParser,
 )