SPRINGFIELD — A single justice of the U.S. Supreme Court is now weighing whether to block Illinois’ assault weapons ban from being enforced while the case is being heard in the Seventh Circuit Court of Appeals.Justice Amy Coney Barrett, who hears applications from the Seventh Circuit, could decide on her own whether to issue an emergency injunction or she could refer the question to the full court for consideration.The case involves both the state’s ban on assault weapons and large capacity magazines as …