By Nathan Ridley Lewis Hamilton described the now completed investigation into Christian Horner’s alleged inappropriate behaviour towards a female colleague at Red Bull “a really important moment for the sport.” Having continually denied the accusations, Horner has now been cleared by Red Bull chiefs, who released a statement on Wednesday afternoon shortly after Hamilton’s comments when previewing this Saturday’s season-opening Bahrain Grand Prix. The Mercedes driver, 39, addressed the controversy prior to the completion of the investigation by saying: “We always have to do more to try to make…