Fix ruff I001 lint error in config.py

Add blank line between standard library and third-party imports to satisfy
ruff's isort rule I001.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: abrichr

openadapt/config.py

@@ -18,6 +18,7 @@
 
 from pathlib import Path
 from typing import Optional
+
 from pydantic_settings import BaseSettings, SettingsConfigDict