By Jose Luis Gonzalez and Daina Beth Solomon CIUDAD JUAREZ, Mexico (Reuters) -Hundreds of migrants bundled in coats and blankets formed a long line in cold winter air at the U.S.-Mexico border on Wednesday, hoping the Christmas period will bring an end to uncertainty over their hopes of securing asylum in the United States. Many hoped entry would be easier after a Dec. 21 deadline for the United States to lift COVID-era restrictions, but the U.S. Supreme Court this week ruled to let the policy, called Title 42, temporarily stay in place. Watching migrants trickle past gates into the United Sta…