A Republican senator is demanding Donald Trump Jr. be subpoenaed over his foreign business dealings and gifts from overseas figures.Sen. John Curtis of Utah called on the Senate Judiciary Committee to investigate the president’s eldest son in a letter sent Monday to the committee’s Republican chairman, Chuck Grassley, and ranking Democrat Dick Durbin. Curtis wants Trump Jr. compelled to testify about his business dealings, foreign relationships, gifts and other benefits he has received.The extraordinary request puts Curtis, 66, at odds with members of his own party, on an issue the Democrats are already pursuing. One of the photos Bettina Trump…