WASHINGTON (Reuters) – Basketball star Brittney Griner landed in the United States on Friday after 10 months in Russian detention that ended with a prisoner swap with arms dealer Viktor Bout who flew home hours earlier to embrace his family on the airport tarmac in Moscow. Thursday’s swap was a rare instance of U.S.-Russian cooperation after Moscow’s invasion of Ukraine earlier this year, although the Kremlin was quick to say it did not show improving relations. The two countries had swapped prisoners in April when Russia released former U.S. Marine Trevor Reed and the United States released R…