Southwest Airlines raised its third-quarter revenue forecast, authorized $2.5 billion in share buybacks and announced a slew of changes to its business as it continues to face pressure from activist hedge fund Elliott Investment Management.The company says its business plan will rake in an additional $4 billion in earnings before interest and taxes by 2027.Southwest said it expects unit revenue growth up to 3% in the third quarter compared to the same period last year – up from previous estimates of a 2% de ...