PRAGUE (Reuters) -PPF Group will install investor Jiri Smejc as its new chief executive from June 15, turning to the longtime investment partner of the Czech company’s late billionaire founder to help navigate the vast business empire through new challenges. PPF has assets worth around 40 billion euros ($42.2 billion)spanning continents and sectors like telecoms, financial services, media, real estate and biotechnology. Its founder, Petr Kellner, died in a helicopter crash in March 2021 while on a skiing trip to Alaska. The 56-year old was the richest Czech businessman at the time of his death…