By Jenna Zucker and Gabriella Borter BUFFALO, N.Y. (Reuters) – A white teenager who fatally shot 10 people in a racist attack at a New York grocery store in a Black neighborhood had been taken into custody and given a mental health evaluation a year ago, but was released after roughly a day, authorities said on Sunday. The suspect, Payton Gendron, 18, surrendered to police on Saturday at the Buffalo, New York, grocery store after what authorities called an act of “racially motivated violent extremism.” He apparently publicized a racist manifesto on the internet. “The evidence that we have unco…