Microsoft Corp.’s MSFT 2.17% LinkedIn said it would shut the version of its professional-networking site that operates in China , marking the end of the last major American social-media network operating openly in the country.LinkedIn, in a statement Thursday, said that it made the decision after "facing a significantly more challenging operating environment and greater compliance requirements in China."Microsoft’s move comes at a time when China’s Communist Party is ratcheting up its control over its largest tech companies , private enterprises and online commentary, as it continues a campaign to assert itself more forcefully across the economy and Chinese society.In...