Docs: Wrong parameter name in AsyncWebCrawler.arun docstring

[AkosLukacs]

Summary

There is an error in the docstring of AsyncWebCrawler.arun: the parameter is called config, not crawler_config.

List of files changed and why

crawl4ai/async_webcrawler.py - see summary

How Has This Been Tested?

This is a docstring change, I assume it will work :)

Summary by CodeRabbit

• Refactor
  • Aligned internal crawler invocation to use a standardized configuration parameter for consistency; no behavior or API changes.
• Documentation
  • Updated docstrings to reflect current configuration parameter naming and usage.
• Style
  • Minor formatting cleanup (newline at end of file).

No user-facing changes or breaking changes in this release.