LOS ANGELES, California—Ditching their signature look that incorporated skin-baring costumes and flashy makeup, members of the Filipino girl group 4th Impact delighted churchgoers at a celebration of the Holy Mass one serene Sunday afternoon. Wearing trousers and long-sleeved tops, sisters Almira, Irene, Mylene, and Celina Cercado came armed with just the powerful vocal chops that had propelled...