By Ben Blanchard and Fabian Hamacher TAIPEI (Reuters) -The United States looks forward to continuity in the Taiwan-U.S. relationship under the new Taiwanese administration and the U.S. commitment to the island is “rock solid”, a former senior U.S. official told Taiwan President Tsai Ing-wen on Monday. Lai Ching-te from Taiwan’s ruling Democratic Progressive Party (DPP) won the presidential election on Saturday as expected and will take office on May 20. In a show of support for the government, a senior administration official said last week that President Joe Biden planned to send an unofficia…