Daniel Ricciardo has almost certainly driven in his final Formula 1 race. There was no official farewell in Singapore, but virtually the entire paddock seemed to know RB’s announcement was coming. Christian Horner has refused to rule out a return for Ricciardo but his stock appears irreparably damaged. This is the second time in three seasons he’s lost his seat, and he’s now suffered the ignominy of being dropped mid-season. That wasn’t purely based on performance. Red Bull wanted to evaluate Liam Lawson as a potential replacement for Sergio Perez, and viewed the final six races as their only …