By Joseph Ax (Reuters) – Louisiana’s Republican-controlled legislature overrode Democratic Governor John Bel Edwards’ veto of a new congressional map, ensuring the state will maintain only a single majority-Black district among its six seats. Edwards rejected the map earlier this month, saying lawmakers should have created a second majority-Black district to account for the Southern state’s large and growing minority population. One-third of the state’s 4.7 million residents are Black. Both legislative chambers voted on Wednesday to invalidate Edwards’ veto largely along party lines, with a tw…