A wealthy financier’s embattled proposal to construct a small winery in the hills north of Santa Rosa earned final approval Tuesday in front of the Sonoma County Board of Supervisors. The 10,000-case winery, proposed by Goldman Sachs partner Henry Cornell, is planned for 40 acres off St. Helena Road, 1.5 miles west of the Napa County line. Cornell owns 215 acres in the area, including vineyards.