By Moira Warburton and Rose Horowitch WASHINGTON (Reuters) -Democrats on a U.S. House committee pressed the top executives of two U.S. gunmakers on Wednesday about their marketing of assault-style rifles that have been used in recent mass shootings, while the executives defended their business. The chief executives of Sturm, Ruger & Co Inc and Daniel Defense Llc, testified at a hearing of the House of Representatives’ Oversight Committee after recent mass shootings in Uvalde, Texas, and Buffalo, New York. The shootings just 10 days apart in May at a Uvalde elementary school and a Buffalo super…