BEIJING (Reuters) – Universal Studios said on Monday it had a sealed an agreement to open a $3.3 billion theme park in Beijing, the culmination of a 13-year effort to enter China’s fast-growing entertainment market. U.S. theme park operators are rushing to build in China, which has few high quality parks but where park revenues have been growing rapidly as city dwellers spend more on entertainment and travel. The Beijing Universal theme park, to be developed with the state firm Beijing Tourism Group Co [BJTGP. …