Fix whitespace in blank line (W293)

- Removed trailing whitespace from blank line in client.py:66
- All flake8 checks now pass

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

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

wikijs/client.py

@@ -63,7 +63,7 @@ class WikiJSClient:
         # Instance variable declarations for mypy
         self._auth_handler: AuthHandler
         self._session: requests.Session
-        
+
         # Validate and normalize base URL
         self.base_url = normalize_url(base_url)