Former zoo owner and reality TV superstar Joe Exotic has been resentenced to 21 years in prison for his role in a murder-for-hire plot, a federal judge said Friday. The resentencing — a shortening of just one year — came despite pleas from his lawyers after an appeals court ordered a new sentence. Supporters were hoping the zookeeper would be freed from prison. The star of the hit Netflix show “Tiger King: Murder, Mayhem and Madness,” whose real name is Joseph Maldonado-Passage, was sentenced to 22 years in January 2020 after he was convicted of hiring two men to kill animal rights activist Ca…