April 30 (Reuters) - BlackRock Inc said on Monday it is hiring two specialists from Goldman Sachs Group Inc to bolster its private equity business in New York, according to a staff memo. Steve Lessar and Konnin Tam will join the world’s largest asset management company from Goldman Sachs this summer, according to the document, which was seen by Reuters. Each will be responsible for expanding BlackRock’s role within a business that effectively enables investors in private companies and funds...