By Anthony Deutsch and Stephen Farrell THE HAGUE/LVIV (Reuters) -The chief prosecutor of the International Criminal Court said on Wednesday he insisted on “zero tolerance” of sexual and gender-based crimes and crimes against children as fighting intensifies in Ukraine. In a rare trip into a conflict zone by a top international prosecutor, Karim Khan said he had met with Ukraine’s foreign minister and prosecutor general during a short visit before going to Poland. He held virtual talks with Ukrainian President Volodymyr Zelenskiy. The ICC started a formal investigation into possible war crimes …