By Rich McKay and Brad Brooks BRUNSWICK, Ga. (Reuters) – The gunman convicted of murdering Ahmaud Arbery, a Black man in Georgia, repeatedly used racist language in text messages with friends, and also shared a music video of a white supremacist singer, jurors at his federal hate crimes trial heard on Wednesday. Travis McMichael, who along with his father and neighbor are on trial, left a racist digital footprint stretching back to at least 2013 and, in the case of the neighbor, continued even after the murder of Arbery, 25, in 2020, FBI agent Amy Vaughan, tasked with processing the digital ev…