SAN DIEGO — The Centers for Disease Control and Prevention has moved to end a controversial border policy that kept thousands of asylum-seekers from requesting protection in the United States over the past two years. The decision Friday leaves the policy, known widely as Title 42, in place until May 23. Enacted in March 2020 by the Trump administration, the policy says that border officials can prevent asylum-seekers and other undocumented migrants from crossing onto U.S. soil and expel them if they do manage to get inside the country. Those expulsions sent many back to the country they crosse…