UPDATE 1 — Grynspan holds lead for next UN chief as race enters decisive stage
(Adds context and details from paragraph 2) By Antoni Slodkowski UNITED NATIONS, Oct 16 (Reuters) — An informal poll by the United Nations Security Council on Friday placed former Costa Rican Vice President Rebeca Grynspan as the narrow frontrunner in the race to become the 10th UN secretary-general, two people close