online_mode harness: the services' key fetch is no login step

Both the vanilla and the Horizon server fetch getPublicKeys in the background, at any moment of a
scenario, so ('unknown', '/publickeys') turned up in four checks (parity run 41243825430 on #5508).
It now stays out of the log, like a bare GET /.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

tools/test_online_mode_parity.py

@@ -121,8 +121,9 @@ class Services:
                         return self.reply(200, {'id': PLAYER_UUID, 'name': query['username'], 'properties': []})
                     return self.reply(204)
                 # A bare `GET /` is a local tool probing every new port (T3 Code does, on the Mac mini), not
-                # the game: none of the services has a root.
-                if url.path != '/':
+                # the game: none of the services has a root. `/publickeys` (getPublicKeys) is both servers
+                # fetching the services' keys in the background, at any moment of a scenario: no login step.
+                if url.path not in ('/', '/publickeys'):
                     with services.lock:
                         services.log.append(('unknown', url.path))
                 self.reply(404, {'error': 'NotFound', 'path': url.path})