By Ron Bousso LONDON (Reuters) – Shell boosted its dividend and share repurchases on Thursday after fourth quarter profits soared to $6.4 billion fueled by higher oil and gas prices and strong gas trading performance. Shell, which moved its headquarters from The Hague to London last month, said it expected to increase its dividend by 4% in the first quarter of 2022 to $0.25 per share. The company also announced it will buy back $8.5 billion worth of shares in the first half of 2022, including $5.5 billion from the sale of its Permian shale assets in the United States. That compares with share …