After a two-year hiatus, deal-making in the U.S. shale patch has hit high gear with the U.S. energy sector leveraging high stock prices to go on a $250 billion buying spree in 2023. Last quarter alone, U.S. oil majors Exxon Mobil Corp. (NYSE:XOM), Chevron Corp. (NYSE:CVX) and Occidental Petroleum (NYSE:OXY) struck deals worth a combined $125 billion to acquire low-cost oilfields with low breakeven oil price. And, activity is not slowing down in the current year. A couple of weeks ago, Midland, Tex.-based Diamondback…