UPDATE 2-Colombia's central bank holds key rate steady at 3.25 pct

* Rate decision was unanimous * Benchmark rate held steady for third straight month * Low inflation leaves policymakers room to stimulate growth By Helen Murphy and Peter Murphy BOGOTA, June 28 (Reuters) - Colombia's central bank held its benchmark lending rate steady for a third straight month on Friday as benign inflation allowed policymakers to keep borrowing costs low enough to nourish anemic growth in the economy. In a unanimous decision, the bank's seven-member board kept the rate at 3.25 percent, as expected, holding borrowing...