STAMFORD — A couple who have left a racial slur spraypainted on their garage will not be charged a $100-a-day blight fine, officials said Wednesday. Heather Lindsay, who lives at the Bull’s Head home with her husband, Lexene Charles, said she will also take up the city on its offer to replace the door on which the word remains in an effort to pressure police to further investigate the incident. Lindsay has said police never investigated the vandalism or claims that neighbors yelled a racial slur at her husband.