By Michael S. Derby NEW YORK (Reuters) -Atlanta Federal Reserve President Raphael Bostic on Friday said that over the last few years some of his personal investing activity inadvertently happened in periods where it was forbidden by U.S. central bank ethics rules at the time. Bostic explained in a note that accompanied revised financial disclosure forms going back to the start of his tenure as Atlanta Fed president in 2017 that trades violating the ethics code were made by financial advisors and were not done under his direction. “Since I assumed office, I have ensured that my assets were held…