WASHINGTON (Reuters) – A group of 21 U.S. lawmakers sent a letter to Facebook chief executive Mark Zuckerberg on Wednesday voicing concern about what they called disinformation on the platform aimed at Spanish speakers about Russia’s invasion of Ukraine. The disinformation is spread by Moscow-backed outlets like RT en Espanol, among others, said the letter joined by Senators Amy Klobuchar and Ben Ray Lujan and Representative Tony Cardenas and 18 others. “Facebook has continuously failed to show it is adequately addressing this problem for Spanish-speaking communities, and the success of Russia…