Major central banks hike rates by 2,700 bps in 2022 * Signs that Bank of Japan could join tightening * Interest rate hikes in emerging economies slowing down further By Karin Strohecker and Vincent Flasseur LONDON, Dec 23 (Reuters) - Major central banks ramped up interest rates at the fastest pace and biggest scale in at least two decades in 2022 as policy makers went all out in the battle to contain...