Mandy Moore is Garnier's newest brand ambassador and will be the face of the brand across  hair color, hair care, hair styling and skin care.   In her debut in this new role, Moore, who has credited her hair color change to brunette as a moment of “real significance,” offers a peek into her life through the brand's new Nutrisse hair color campaign.   The creative, which will begin running on tomorrow  and includes print, TV, digital and social media content that reflects Mo...