LONDON (Reuters) -Russian officials lined up to celebrate the downfall of Boris Johnson on Thursday, with a leading tycoon casting the British leader as a "stupid clown" who had finally got his just reward for arming Ukraine against Russia.Johnson was expected to announce his resignation after he was abandoned by ministers and his Conservative Party's lawmakers who said he was no longer fit to govern. The Kremlin said it too was no fan of the British leader, whose parents named him Boris after a White Russian emigre."He doesn't like us, we don't like him either," Kremlin spokesman Dmitry Peskov said.