A drone has been found to have played a critical role for the would-be assassin of former President Donald Trump. Investigators working to unravel the circumstances surrounding the July 13 shooting discovered the drone was used to collect aerial footage of Pennsylvania’s Butler Farm Show grounds, The Wall Street Journal reported Friday. Thomas Matthew Crooks, 20, flew the drone over the area where Trump’s rally was set to take place later in the day before ultimately climbing a nearby roof and firing a rifle, hitting the former president, killing one rallygoer and injuring others. Crooks secur…