By Cassandra Garrison and Andrea Shalal MEXICO CITY/WASHINGTON (Reuters) -The governors of the Inter-American Development Bank (IDB) voted on Monday to fire Mauricio Claver-Carone, two people with knowledge of the vote said, after an investigation showed the only American president in the bank’s 62-year history had an intimate relationship with a subordinate. The 14 directors had voted unanimously on Thursday to recommend firing Claver-Carone after an independent ethics investigation found evidence he had engaged in an intimate relationship with a senior staffer for whom he had made employment…