Parafin, a financial-technology startup run by former Robinhood Markets Inc. employees, raised $100 million in a late-stage round that may signal renewed investment in a category that has struggled to navigate a dry-up in venture capital funding. The financing, which comes at a $750 million valuation, was led by Notable Capital, with participation from Redpoint Ventures, the San Francisco-based firm said in a statement Tuesday. Existing investors Ribbit Capital, Thrive Capital, and GIC Pte, Sin...