By Nandita Bose and Humeyra Pamuk WASHINGTON (Reuters) -U.S. basketball star Brittney Griner has been released in a prisoner swap with Russia in exchange for arms dealer Viktor Bout and was heading home on Thursday, ending what President Joe Biden called months of “hell” for her and her wife. The swap was arranged after months of talks during a time of high tension between the two countries after Russia’s February invasion of Ukraine. As Griner was on a flight bound for Texas, Bout arrived in Moscow and hugged his mother and wife after stepping onto the tarmac, television images showed. Griner…