WNBA star Brittney Griner showed up without notice at the Rev. Al Sharpton’s annual convention in Manhattan on Thursday, marking her first public appearance in New York since her release from a Russian prison. Griner, who was behind bars in Russia for 10 months last year after being caught at a Moscow airport with a vial of cannabis vaping oil, voiced gratitude to Sharpton for the role he played in helping broker her release back to the U.S. in December. “It means everything to be here today,” Griner said in brief remarks after being introduced by Sharpton at his National Action Network conven...