Egypt’s Ahmed Helmy and Hend Sabri — who are two of the Arab world’s most bankable stars — are set to be paired onscreen for the first time in upcoming Cairo-set feature “His Weakest Creatures” by Egyptian director Omar Hilal, who made a splash with breakout hit “Voy! Voy! Voy.” In “His Weakest Creatures,” Helmy — who is known locally for smash hit comedies such as “Wahed Tany” and “X-Large” –—will tackle a role layered with dramatic gravitas, playing a principled zoologist who works in Cairo’s