httpx logs every request URL at INFO level, and the GNews search URL
carries the API key as a `?token=` query param, so GNEWS_API_KEY was
written in plaintext into the pod logs on every news query. Raise the
httpx/httpcore loggers to WARNING so request URLs never reach INFO.
The bot's own GNews log lines only print the sanitised keyword query
(NewsClient._build_query), never the token, so they are unaffected.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>