safety: setup-time message about updating unsafe-domains cache

Previous status message in the download function has been demoted to
debug level, but it's still nice to confirm at startup that an update
attempt is being made.

Author: dgw

sopel/modules/safety.py

@@ -120,6 +120,7 @@ def setup(bot: Sopel):
             # Python on Windows throws an exception if the file is in use
             LOGGER.warning('Could not delete %s: %s', old_file, str(err))
 
+    LOGGER.info('Ensuring unsafe domain list is up-to-date (safety plugin startup)')
     update_local_cache(bot, init=True)