Costa Rica's Grynspan extends lead in informal UN chief poll, sources say

By Antoni SlodkowskiUNITED NATIONS, Oct 30 (Reuters) - An informal poll by the United Nations Security Council on Friday showed former Costa Rican Vice President Rebeca Grynspan extended her lead as frontrunner in the race to become the 10th UN secretary-general, two people close ‌to the process said.Grynspan got 11 votes in favor and 4 against on the 15-member council…