SAN DIEGO — For nearly 50 years, Sirhan Sirhan has been consistent: He says he doesn’t remember fatally shooting Sen. Robert F. Kennedy in a crowded kitchen pantry of the Ambassador Hotel in Los Angeles.The Jerusalem native, now 71, has given no inkling that he will change his version of events at his 15th parole hearing today in San Diego. He is serving a life sentence that was commuted from death when the California Supreme Court briefly outlawed capital punishment in 1972.During his previous parole hearing in 2011 …