Salvors have lightered bulk diesel fuel from a luxury yacht that grounded on a reef just off Flamenco Beach in Culebra, Puerto Rico, the U.S. Coast Guard said.The 72-foot sailing catamaran Obsession was reportedly traveling with four people on board from Puerto Rico to the British Virgin Islands when it struck a reef during a stop in Culebra on July 21. No injuries were reported.The fuel removal was conducted by Resolve Marine and Clean Harbors, LLC crews and consisted of the estimated 800 to 1…